Bean leaf beetles: Predicted winter mortality
by Marlin E. Rice, Department of Entomology, and Rich Pope, Departments of Entomology and Plant Pathology
During the last 17 years, the bean leaf beetle has undergone tremendous population changes in Iowa. From 1989 to 1996, the populations (both first generation and second generation) were relatively insignificant and the insect hardly could even be considered a serious pest. But in 1997, the population in central Iowa began to accelerate nearly yearly until it reached a historical high in 2002. Populations that year were nearly 400 times larger than those of the mid-1990s. Since that time, the population has returned to more normal levels and is similar to what we witnessed at the beginning of the beetle explosion in the late 1990s.
Bean leaf beetle (red phase).Bean leaf beetle (red phase).
So what are the primary reasons for the tremendous population increases several years ago? We believe there are two obvious answers--milder winters and earlier planting of soybeans. As the average winter temperature began to get warmer over several years, so did the insect population. A drop in the winter temperature during 2000-2001 brought a small decline in the bean leaf beetles, but the temperature went up the following winter and the insects rebounded. Earlier planting (and emerging) of soybeans is another primary reason. Early soybeans allow beetles more time to lay their eggs before they die as opposed to later emerging fields where fewer eggs can be laid before the beetles expire.
But since 2002, the bean leaf beetle has hit on "hard times." Late-season spraying for soybean aphids during July and August has greatly reduced the second generation. Each year that we spray aphids, fewer beetles are alive to go into hibernation. A resulting benefit from the soybean aphid applications is that the bean leaf beetle is now relegated to secondary pest status in many areas.
Predicted mortality of overwintering bean leaf beetles in Iowa crop reporting districts as of April 2007.Predicted mortality of overwintering bean leaf beetles in Iowa crop reporting districts as of April 2007.
The beetles will be back again this spring--some were seen in Ames on April 29. Based on this past winter, we predict that the survival of overwintering bean leaf beetles was very similar to what we have seen the past couple of years. In other words, great conditions for the beetles throughout most of the state except for the northern third of the state (see map). Even though bean leaf beetle populations are relatively low, the earliest emerging fields in an area (such as a township) should be closely scouted for this pest and managed if necessary. Beetles are highly attracted to these early emerging fields. Fields that should be of greatest concern from this insect, and the virus it spreads (bean pod mottle virus), are food-grade soybeans and seed beans. Reductions in yield and seed quality can be significant in these fields from these two pests. Information on managing this pest complex will be printed in an upcoming newsletter, can be found in today's and last week's newsletter, or see Bean leaf beetle and bean pod mottle virus management: An integrated approach.
Marlin E. Rice is a professor of entomology with extension and research responsibilities. Rich Pope is an extension program specialist in entomology with responsibilities in integrated pest management and pesticide applicator training.
This article originally appeared on page 129 of the IC-498 (8) -- April 30, 2007 issue.
Kamis, 15 Oktober 2009
Jumat, 09 Oktober 2009
This WAYNE'S WORD Is Dedicated To
The Amazing Insects Known As Beetles
[No, not the two-legged musical variety from England, but the six-legged type with
a chitinous exoskeleton and a pair of leathery elytra covering their flight wings].
1. Are Rhinoceros & Hercules Beetles A Threat To Bikers?
2. Do Lightning Beetles Cause Forest Fires?
3. Is Spanish Fly Really A Fly From Spain?
4. Can Short Circuit Beetles Cause Blackouts?
5. Can Sunscreen Lotions Protect You From Blister Beetles?
6. Is It Politically Correct To Call Ladybird Beetles Ladybugs?
7. Do Dung Beetles Enjoy Rolling In Manure All Day?
8. Do Extraterrestrials Read WAYNE'S WORD?
An assortment of beetles.
One Fifth Of All The 1.5 Million Living Species On Earth Are Beetles!
There are more than 800,000 species of insects on earth, more than all the other plants and animals combined. Of this great number of insects, nearly half are beetles. Unlike other insects, beetles have a pair of leathery protective wings called elytra that cover their membranous flight wings. During flight, the elytra are spread apart and the two flight wings are unfolded and extended. Beetles come in a variety of shapes and colors, from red "ladybugs" and metallic green fig beetles to lightning beetles that glow in the dark and huge horned beetles resembling a miniature rhinoceros. Colorful beetles are used for jewelry and pins, and shiny tropical scarab beetles are strung together to make unusual necklaces. Beetles range in size from less than a millimeter (1/100 of an inch) to tropical giants over six inches long. The largest giants may weigh 40 million times more than their lilliputian relatives.
The world's largest beetle: Titanus giganteus, a member of the Cerambycidae native to South America. These large beetles can measure up to 170 mm (over 6 inches in length). Although the larvae are wood borers, the adults can inflict a painful bite. An adult male apparently bit and shattered a plastic ruler used as a size relationship by a photographer. One can only imagine what the powerful mandibles could do to your fingernail (or your finger). The giant beetle is compared with a minute flower beetle enclosed in a red circle. The flower beetle is only 4 mm in length (about 1/6th of an inch), smaller than the "foot" of Titanus giganteus. Other size relationships in this photo include the "head" of an ordinary straight pin, the "eye" of a sewing needle, and a millimeter ruler.
Size Relationships Used In Wayne's Word
One of the most amazing is the Hercules beetle (Dynastes hercules), native to the rain forests of Central America. This spectacular beetle has two enormous curved horns and looks like a creature from the age of dinosaurs. In fact, it is truly amazing that this monster can actually fly. For many years, a bronze sculpture of this remarkable beetle stood at the entrance to the San Diego Museum of Natural History in Balboa Park. If all the different species of plants and animals on earth were randomly lined up, every fifth one would be a beetle. Beetles have taken seriously the injunction "Be fruitful and multiply and replenish the earth."
Dynastes hercules, a spectacular hercules beetle from Costa Rica.
Male southwestern hercules beetle (Dynastes granti)
on display at the Red Rock State Park Visitor Center.
Dynastes granti, a female southwestern hercules beetle from Arizona.
Stag Beetle Family (Lucanidae)
Cottonwood stag beetle (Lucanus mazama).
The earliest known prehistoric beetles date back about 230 million years ago, a time when dinosaurs roamed the earth. With the advent of flowering plants about 65 million years ago, speciation in beetles occurred at an astronomical rate as they began to exploit the rapidly evolving angiosperms. Hard bodies of beetles preserve very well, and fossil records of beetles are found throughout the evolution of flowering plants. One of the most interesting locations for beetle fossils is the La Brea formation at Mckittrick, California where numerous Pleistocene animals became entomed in tar pits over 10 million years ago. The tar pits were formed as crude oil seeped to the surface through fissures in the earth's crust. Evaporation of the oils resulted in a thick, sticky substance resembling asphalt. Some of the beetles embedded in these formations are perfectly preserved in every detail.
This beetle became trapped in a tar pit nearly 11 million years ago, at a time when large glaciers dominated the landscape in North America. The elytra (wing covers) of this beetle are perfectly preserved. The beetle appears to be a streamlined water beetle, possibly belonging to the family Dytiscidae.
A modern-day water beetle in the family Hydrophilidae. This is probably the giant black water beetle (Hydrophilus triangularis). Water beetles are descendants of terrestrial insects and have evolved a number of adaptations for living in water. The bodies are streamlined to reduce drag as they swim. The flattened short legs are fringed with hairs and serve to propel the beetle through water. While submersed these beetles obtain oxygen from a bubble of air stored under their inner wings (elytra) and along the ventral surface of their thorax.
Volumes have been written about the amazing world of beetles. Adult short circuit beetles (Scobicia declivis) bore into lead sheathing of telephone cables causing short circuiting when moisture enters the small holes. Trunks of native California fan palms in the southwestern U.S. often contain large circular tunnels, the work of huge boring larvae (Dinapate wrightii), a member of the family Bostrichidae. The hardwood floor beneath a palm trunk section at the San Diego Museum of Natural History was deeply grooved by one of these larvae. The adult beetle is truly bizarre. In the late 1800's museums paid up to $1,000 to an enterprising collector for one of these striking beetles. The collector (probably a business major) reportedly inflated the value of his merchandise by keeping their exact location a secret.
The larva and adult of the palm-boring beetle (Dinapate wrightii).
See Palm Wood Bored By Larva Of Dinapate wrighii
Stout's hardwood borer (Polycaon stouti), another member of the family Bostrichidae. This beetle has very destructive larvae, particularly if you have wood construction in your home made of oak and maple. The larvae of this beetle can even bore into furniture!
Bombardier beetles (Brachinus spp.) inject an explosive mixture of hydroquinone, hydrogen peroxide plus several potent catalysts into a reaction chamber in the abdomen. Catalase breaks down the hydrogen peroxide into water and oxygen gas. Peroxidase oxidizes hydroquinone into benzoquinone. The mixture of chemicals and enzymes volatilizes instantly upon contact with the air, generating a puff of "smoke"" and an audible popping sound. This caustic flatulence is totally controlled by the beetle, otherwise it might accidentally blow up its rear end. The explosive discharge apparently discourages predators, either by chemical irritation, heat or repugnance. The temperature of the explosive mixture of gasses and fluids is over 100 degrees Celsius, the boiling point of water. This astonishing chemical defense mechanism is discussed by D.J. Aneshansley and T. Eisner (1969) in Science Vol. 165: 61-63.
Bombardier beetles of the genus Brachinus, a member of the large ground beetle family (Carabidae). These small beetles are about 13 mm long (1/2 inch). They are fairly common in southern California, particularly near streams, lakes and marshy areas. The wing covers (elytra) are dark blue-brown with a contrasting reddish-orange head and prothorax.
The body fluids of some blister beetles of the family Meloidae contain cantharidin, a substance that causes severe irritation and blistering of skin. This chemical is very sensitive to mucous membranes and is the active ingredient of "Spanish-fly," made from the ground up bodies of a European blister beetle (Lytta vesicatoria) . Although it has been used as a counterirritant, its use as an aphrodisiac is very unwise unless you are raising livestock or chickens.
Soldier blister beetles of the genus (Tegrodera).
A desert blister beetle (Lytta magister) on rabbitbrush (Chrysothamnus nauseosus).
The inflated blister beetle (Cysteodemus armatus), a curious beetle with a small head and inflated abdomen. Because it superficially resembles a spider it is sometimes called the desert spider beetle. This beetle feeds on ephemeral wildflowers as it scurries across sandy riverbeds and washes. The pitted back has several color variations.
Inflated Blister Beetles In Anza-Borrego Desert
See Desrt Blister Beetle In Anza-Borrego Desert
See An Amazing Bombardier Beetle (Brachinus sp.)
A metallic green fig beetle (Cotinus texana), so named because it is often found feeding on fig fruits during the warm summer months in southern California. It is also fond of other ripe, juicy fruits, such as peaches and plums. These attractive beetles spend their juvenile larval stage in the ground, often beneath manure piles, compost and haystacks.
A metallic green fig beetle (Cotinus texana) gorging itself inside a fleshy, ripe syconium of the Calimyrna fig (Ficus carica). Although masses of minute, aggressive Argentine ants (Iridomyrmex humilis) are also foraging in the syconium, the beetle is protected by a tough, impervious exoskeleton.
See: Beware Of The Argentine Ants
The pine sawyer is one of the largest beetles in urbanized areas of southern California. It belongs to the long-horned beetle family (Cerambycidae) The large, pale larva, up to 2 1/2 inches (6.3 cm) long, feeds on the wood of fallen logs and old conifer stumps. The adult beetle in above photo is over 3 inches long (including the extended antennae). It has a pair of powerful jaws (mandibles) that are capable of inflicting a painful pinch. At least they can leave an imprint on a piece of cardboard! The adults emerge from subterranean stumps in early summer. They are nocturnal and are attracted to lights. It is always a surprise when one of these big beetles lands on your window screen.
An adult pine sawyer beetle (Ergates spiculatus).
[Thanks to Jim Hogue at CSUN for the correct ID of this species.]
Another long-horned wood-boring beetle (Prionus californicus). The
antennal segments of the male (in this photo) are conspicuously lobed.
The Amazing Insects Known As Beetles
[No, not the two-legged musical variety from England, but the six-legged type with
a chitinous exoskeleton and a pair of leathery elytra covering their flight wings].
1. Are Rhinoceros & Hercules Beetles A Threat To Bikers?
2. Do Lightning Beetles Cause Forest Fires?
3. Is Spanish Fly Really A Fly From Spain?
4. Can Short Circuit Beetles Cause Blackouts?
5. Can Sunscreen Lotions Protect You From Blister Beetles?
6. Is It Politically Correct To Call Ladybird Beetles Ladybugs?
7. Do Dung Beetles Enjoy Rolling In Manure All Day?
8. Do Extraterrestrials Read WAYNE'S WORD?
An assortment of beetles.
One Fifth Of All The 1.5 Million Living Species On Earth Are Beetles!
There are more than 800,000 species of insects on earth, more than all the other plants and animals combined. Of this great number of insects, nearly half are beetles. Unlike other insects, beetles have a pair of leathery protective wings called elytra that cover their membranous flight wings. During flight, the elytra are spread apart and the two flight wings are unfolded and extended. Beetles come in a variety of shapes and colors, from red "ladybugs" and metallic green fig beetles to lightning beetles that glow in the dark and huge horned beetles resembling a miniature rhinoceros. Colorful beetles are used for jewelry and pins, and shiny tropical scarab beetles are strung together to make unusual necklaces. Beetles range in size from less than a millimeter (1/100 of an inch) to tropical giants over six inches long. The largest giants may weigh 40 million times more than their lilliputian relatives.
The world's largest beetle: Titanus giganteus, a member of the Cerambycidae native to South America. These large beetles can measure up to 170 mm (over 6 inches in length). Although the larvae are wood borers, the adults can inflict a painful bite. An adult male apparently bit and shattered a plastic ruler used as a size relationship by a photographer. One can only imagine what the powerful mandibles could do to your fingernail (or your finger). The giant beetle is compared with a minute flower beetle enclosed in a red circle. The flower beetle is only 4 mm in length (about 1/6th of an inch), smaller than the "foot" of Titanus giganteus. Other size relationships in this photo include the "head" of an ordinary straight pin, the "eye" of a sewing needle, and a millimeter ruler.
Size Relationships Used In Wayne's Word
One of the most amazing is the Hercules beetle (Dynastes hercules), native to the rain forests of Central America. This spectacular beetle has two enormous curved horns and looks like a creature from the age of dinosaurs. In fact, it is truly amazing that this monster can actually fly. For many years, a bronze sculpture of this remarkable beetle stood at the entrance to the San Diego Museum of Natural History in Balboa Park. If all the different species of plants and animals on earth were randomly lined up, every fifth one would be a beetle. Beetles have taken seriously the injunction "Be fruitful and multiply and replenish the earth."
Dynastes hercules, a spectacular hercules beetle from Costa Rica.
Male southwestern hercules beetle (Dynastes granti)
on display at the Red Rock State Park Visitor Center.
Dynastes granti, a female southwestern hercules beetle from Arizona.
Stag Beetle Family (Lucanidae)
Cottonwood stag beetle (Lucanus mazama).
The earliest known prehistoric beetles date back about 230 million years ago, a time when dinosaurs roamed the earth. With the advent of flowering plants about 65 million years ago, speciation in beetles occurred at an astronomical rate as they began to exploit the rapidly evolving angiosperms. Hard bodies of beetles preserve very well, and fossil records of beetles are found throughout the evolution of flowering plants. One of the most interesting locations for beetle fossils is the La Brea formation at Mckittrick, California where numerous Pleistocene animals became entomed in tar pits over 10 million years ago. The tar pits were formed as crude oil seeped to the surface through fissures in the earth's crust. Evaporation of the oils resulted in a thick, sticky substance resembling asphalt. Some of the beetles embedded in these formations are perfectly preserved in every detail.
This beetle became trapped in a tar pit nearly 11 million years ago, at a time when large glaciers dominated the landscape in North America. The elytra (wing covers) of this beetle are perfectly preserved. The beetle appears to be a streamlined water beetle, possibly belonging to the family Dytiscidae.
A modern-day water beetle in the family Hydrophilidae. This is probably the giant black water beetle (Hydrophilus triangularis). Water beetles are descendants of terrestrial insects and have evolved a number of adaptations for living in water. The bodies are streamlined to reduce drag as they swim. The flattened short legs are fringed with hairs and serve to propel the beetle through water. While submersed these beetles obtain oxygen from a bubble of air stored under their inner wings (elytra) and along the ventral surface of their thorax.
Volumes have been written about the amazing world of beetles. Adult short circuit beetles (Scobicia declivis) bore into lead sheathing of telephone cables causing short circuiting when moisture enters the small holes. Trunks of native California fan palms in the southwestern U.S. often contain large circular tunnels, the work of huge boring larvae (Dinapate wrightii), a member of the family Bostrichidae. The hardwood floor beneath a palm trunk section at the San Diego Museum of Natural History was deeply grooved by one of these larvae. The adult beetle is truly bizarre. In the late 1800's museums paid up to $1,000 to an enterprising collector for one of these striking beetles. The collector (probably a business major) reportedly inflated the value of his merchandise by keeping their exact location a secret.
The larva and adult of the palm-boring beetle (Dinapate wrightii).
See Palm Wood Bored By Larva Of Dinapate wrighii
Stout's hardwood borer (Polycaon stouti), another member of the family Bostrichidae. This beetle has very destructive larvae, particularly if you have wood construction in your home made of oak and maple. The larvae of this beetle can even bore into furniture!
Bombardier beetles (Brachinus spp.) inject an explosive mixture of hydroquinone, hydrogen peroxide plus several potent catalysts into a reaction chamber in the abdomen. Catalase breaks down the hydrogen peroxide into water and oxygen gas. Peroxidase oxidizes hydroquinone into benzoquinone. The mixture of chemicals and enzymes volatilizes instantly upon contact with the air, generating a puff of "smoke"" and an audible popping sound. This caustic flatulence is totally controlled by the beetle, otherwise it might accidentally blow up its rear end. The explosive discharge apparently discourages predators, either by chemical irritation, heat or repugnance. The temperature of the explosive mixture of gasses and fluids is over 100 degrees Celsius, the boiling point of water. This astonishing chemical defense mechanism is discussed by D.J. Aneshansley and T. Eisner (1969) in Science Vol. 165: 61-63.
Bombardier beetles of the genus Brachinus, a member of the large ground beetle family (Carabidae). These small beetles are about 13 mm long (1/2 inch). They are fairly common in southern California, particularly near streams, lakes and marshy areas. The wing covers (elytra) are dark blue-brown with a contrasting reddish-orange head and prothorax.
The body fluids of some blister beetles of the family Meloidae contain cantharidin, a substance that causes severe irritation and blistering of skin. This chemical is very sensitive to mucous membranes and is the active ingredient of "Spanish-fly," made from the ground up bodies of a European blister beetle (Lytta vesicatoria) . Although it has been used as a counterirritant, its use as an aphrodisiac is very unwise unless you are raising livestock or chickens.
Soldier blister beetles of the genus (Tegrodera).
A desert blister beetle (Lytta magister) on rabbitbrush (Chrysothamnus nauseosus).
The inflated blister beetle (Cysteodemus armatus), a curious beetle with a small head and inflated abdomen. Because it superficially resembles a spider it is sometimes called the desert spider beetle. This beetle feeds on ephemeral wildflowers as it scurries across sandy riverbeds and washes. The pitted back has several color variations.
Inflated Blister Beetles In Anza-Borrego Desert
See Desrt Blister Beetle In Anza-Borrego Desert
See An Amazing Bombardier Beetle (Brachinus sp.)
A metallic green fig beetle (Cotinus texana), so named because it is often found feeding on fig fruits during the warm summer months in southern California. It is also fond of other ripe, juicy fruits, such as peaches and plums. These attractive beetles spend their juvenile larval stage in the ground, often beneath manure piles, compost and haystacks.
A metallic green fig beetle (Cotinus texana) gorging itself inside a fleshy, ripe syconium of the Calimyrna fig (Ficus carica). Although masses of minute, aggressive Argentine ants (Iridomyrmex humilis) are also foraging in the syconium, the beetle is protected by a tough, impervious exoskeleton.
See: Beware Of The Argentine Ants
The pine sawyer is one of the largest beetles in urbanized areas of southern California. It belongs to the long-horned beetle family (Cerambycidae) The large, pale larva, up to 2 1/2 inches (6.3 cm) long, feeds on the wood of fallen logs and old conifer stumps. The adult beetle in above photo is over 3 inches long (including the extended antennae). It has a pair of powerful jaws (mandibles) that are capable of inflicting a painful pinch. At least they can leave an imprint on a piece of cardboard! The adults emerge from subterranean stumps in early summer. They are nocturnal and are attracted to lights. It is always a surprise when one of these big beetles lands on your window screen.
An adult pine sawyer beetle (Ergates spiculatus).
[Thanks to Jim Hogue at CSUN for the correct ID of this species.]
Another long-horned wood-boring beetle (Prionus californicus). The
antennal segments of the male (in this photo) are conspicuously lobed.
The People's Car"
Advertisement from c.1939 says "Five marks a week you must put aside - If in your own car you want to ride!")
Starting in 1931, Ferdinand Porsche and Zündapp developed the "Auto für Jedermann" (car for everybody). Porsche already preferred the flat-4 cylinder engine, but Zündapp used a water-cooled 5-cylinder radial engine. In 1932, three prototypes were running.[4] All of those cars were lost during the war, the last in a bombing raid over Stuttgart in 1945.
Porsche Type 12, 1931/32 by Zündapp Nürnberg
In 1933, Adolf Hitler gave the order to Ferdinand Porsche to develop a "Volks-Wagen" . The concept may have been influenced by an earlier design of the same name, created by Josef Ganz, a Jewish engineer who had designed a "Volks-Wagen" in the 1920s.[5] The name means "people's car" in German, in which it is pronounced [ˈfolksvɑːgən]). Hitler required a basic vehicle capable of transporting two adults and three children at 100 km/h (62 mph). The "People's Car" would be available to citizens of the Third Reich through a savings scheme at 990 Reichsmark, about the price of a small motorcycle (an average income being around 32RM a week).[6]
Erwin Komenda, Porsche's chief designer, was responsible for the design and style of the car. But production only became worthwhile when finance was backed by the Third Reich. War started before large-scale production of the Volkswagen started, and manufacturing shifted to producing military vehicles. Production of civilian VW automobiles did not start until post-war occupation.
[edit] The military Beetle and production up to 1945
Kommandeurwagen
Initially called the Porsche 60 by Ferdinand Porsche, it was officially named the KdF-Wagen when the project was launched. The name refers to Kraft durch Freude (Strength Through Joy), the official leisure organization in the Third Reich. It was later known as the Type 1, but became more commonly known as the Beetle after World War II.
Prototypes appeared from 1931; the first were produced by Zündapp in Nürnberg, the Porsche Type 12. The next prototype series (Porsche Type 32) were built in 1933 by NSU, another motorcycle company. When Chrysler brought out its DeSoto Airflow coupe in 1934, final design for the car was decided.
In October 1935 the first Type 60 was ready. In 1935 testing of the "V3" started. The "VW30" prototypes had further testing in 1937. All cars already had the distinctive round shape and the air-cooled, rear-mounted engine, except for the Type 12, Zündapp preferred a 5-cylinder radial watercooled engine.
The factory had only produced a handful of cars by start of the war in 1939. Consequently, the first volume-produced versions of the car's chassis were military vehicles, the Kübelwagen Type 82 (approx. 52,000 built) and the amphibious Schwimmwagen Type 166 (approx. 14,000 built).
The car was designed to be as simple as possible mechanically, so that there was less to go wrong; the aircooled 985 cc 25 horsepower (19 kW) motors proved especially effective in actions of the German Afrika Korps in Africa's desert heat. This was due to the built-in oil-cooler, and the superior performance of the flat-4 engine configuration. The innovative suspension design used compact torsion bars instead of coil or leaf springs. The Beetle is more or less airtight and will float on water, indeed it is hard to slam the door on one since the difference in air pressure pushes it back before it shuts.
The model village of Stadt des KdF-Wagens was created in Lower Saxony in 1938 for the benefit of the workers at the factory.
A handful of Beetles were produced specifically for civilians, primarily for the Nazi elite, in the years 1940–1945, but production figures were small. Because of gasoline shortages, a few wartime "Holzbrenner" Beetles were fueled by wood pyrolysis gas producers under the hood. In addition to the Kübelwagen, Schwimmwagen, and handful of others, the factory managed another wartime vehicle: the Kommandeurwagen; a Beetle body mounted on the Kübelwagen chassis.
669 Kommandeurwagens were produced up to 1945, when all production was halted because of heavy damage to the factory by Allied air raids. Much of the essential equipment had already been moved to underground bunkers for protection, which let production resume quickly after hostilities ended.
[edit] Conflict with Tatra
Much of the Beetle’s design was inspired by the advanced Czech Tatra cars, designed under chief engineer Hans Ledwinka. In particular, Tatra’s T97 and T77a models show striking similarities with the later Volkswagen from many angles.
Thirties Tatras used streamlined bodies with rear-mounted engines. The T97,[7] which is widely held to be the closest Tatra model to Porsche’s Volkswagen, had a four-cylinder horizontally-opposed (‘flat four’) air-cooled engine. On a smaller scale, the company’s V570, a prototype for a smaller car, also shows quite a resemblance to the later German car.
But it wasn’t just Tatra’s aerodynamic styling that influenced Porsche. Tatra had pioneered the use of air-cooling in road vehicle engines with the original T77 in 1934. Air-cooling was demanding technologically, but desirable: there was no anti-freeze in the 1930s, so a vehicle could not be left parked for long in cold weather with its coolant in situ. Tatra’s wealthy customers could afford to pay for advanced technology, but Ferdinand Porsche was out on a limb in specifying air-cooling for his people’s car. In the end, it was subsidies from the Nazi government that paid for Porsche’s engineering good taste and brought the convenience of air-cooling to a mass audience — albeit only after the second world war.
According to the book Car Wars, Adolf Hitler called the Tatra 'the kind of car I want for my highways'.[8] In the same book, it is said that Ferdinand Porsche admitted ‘to have looked over Ledwinka’s shoulder’ while designing the Volkswagen.[8] Tatra launched a lawsuit, but this was stopped when Germany invaded Czechoslovakia. At the same time, Tatra was forced to stop producing the T97. The matter was re-opened after WW2 and in 1961 Volkswagen paid Tatra 3,000,000 Deutsche Marks in compensation. These damages meant that Volkswagen had little money for the development of new models and the Beetle's production life was necessarily extended. Tatra ceased producing passenger cars in 1950, then resumed again in 1954 as a manufacturer of large luxurious cars and limousines under various Communist governments in Czechoslovakia. Even the company’s last limousines were rear-engined and air cooled.
Tatra is now a truck manufacturer. All its engines are still air-cooled, despite the demands of modern emissions regulations.
[edit] Post-war production and boom
In occupied Germany, the Allies followed the Morgenthau plan to remove all German war potential by complete or partial pastoralization. As part of this, in the Industrial plans for Germany, the rules for which industry Germany was to be allowed to retain were set out. German car production was set at a maximum of 10% of the 1936 car production numbers.[9]
The Volkswagen factory at Wolfsburg was handed over by the Americans to British control in 1945; it was to be dismantled and shipped to Britain.[10] Thankfully for Volkswagen, no British car manufacturer was interested in the factory; "the vehicle does not meet the fundamental technical requirement of a motor-car ... it is quite unattractive to the average buyer ... To build the car commercially would be a completely uneconomic enterprise."[10] The factory survived by producing cars for the British Army instead.[10] Allied dismantling policy changed in late 1946 to mid 1947, although heavy industry continued to be dismantled until 1951. In March 1947 Herbert Hoover helped change policy by stating
"There is the illusion that the New Germany left after the annexations can be reduced to a 'pastoral state'. It cannot be done unless we exterminate or move 25,000,000 people out of it."[11]
The re-opening of the factory is largely accredited to British Army officer Major Ivan Hirst (1916–2000).[12] Hirst was ordered to take control of the heavily bombed factory, which the Americans had captured. His first task was to remove an unexploded bomb which had fallen through the roof and lodged itself between some pieces of irreplaceable production equipment; if the bomb had exploded, the Beetle's fate would have been sealed. Hirst persuaded the British military to order 20,000 of the cars,[6] and by 1946 the factory was producing 1,000 cars a month. During this period the car and its town changed their Nazi-era names to Volkswagen (people's car) and Wolfsburg, respectively. The first 1,785 Beetles were made in a factory near Wolfsburg in 1945.
The jeweled one-millionth VW Beetle
Following the Army-led restart of production,former Opel manager (and formerly a detractor of the VW*) Heinz Nordhoff was appointed director of the Volkswagen factory,[6] under whom production increased dramatically over the following decade, with the one-millionth car coming off the assembly line by 1955. During this Post-war period, the Beetle had superior performance in its category with a top speed of 115 km/h (71 mph) and 0-100 km/h (0-60 mph) in 27.5 seconds on 36 mpg (15 km/l) for the standard 25 kw (33 hp) engine. This was far superior to the Citroën 2CV and Morris Minor, and even competitive with more modern small cars like the Mini of the 1960s and later.
* According to the book Small Wonder by Walter Henry Nelson:
"The engine fires up immediately without a choke. It has tolerable road-handling and is economical to maintain. Although a small car, the engine has great elasticity and gave the feeling of better output than its small nominal size."
But opinion in the United States was not flattering, perhaps because of the characteristic differences between the American and European car markets. Henry Ford II once described the car as 'a little box.'[citation needed] The Ford company was offered the entire VW works after the war for free. Ford's right-hand man Ernest Breech was asked what he thought, and told Henry II, "What we're being offered here, Mr. Ford, isn't worth a damn!" With that, the Ford Motor Company lost out on the chance to build the world's most popular car since his grandfather's own Model-T.
During the 1950s, the car was modified progressively: the obvious visual changes mostly concerned the windows.[13] In March 1953, the small oval two-piece rear window was replaced by a slightly larger single-piece window. More dramatically, in August 1957 a much larger full width rear window replaced the oval one. 1964 saw the introduction of a widened cover for the light over the rear licence plate. Towards the end of 1964, the height of the side windows and windscreen grew slightly, giving the cabin a less pinched look: this coincided with the introduction of a very slightly curved ("panoramic") windscreen, though the curve was barely noticeable. The same body appeared during 1966, with a 1300 cc engine in place of the 1200 cc engine: it was only in the 1973 model Super Beetle that the beetle acquired an obviously curved windscreen. The flat windscreen remained on the standard beetle.
There were also changes under the bonnet. In 1954, by adding 2mm to the bore, Volkswagen increased the engine capacity from 1,131 to 1,192.[14] This coincided with upgrades to various key components including a redesign of the crankshaft. The result was a power uplift from 33 bhp to a claimed 40 bhp and an improvement in the engine's free revving abilities without compromising the torque characteristics at lower engine speeds.[14] At the same time, compression ratios were progressively raised as, little by little, the octane ratings of available basic fuel was raised in major markets during the 1950s and 1960s.[14]
During the 1960s and early 1970s, advertising campaigns and a reputation for reliability and sturdiness helped production figures to surpass the levels of the previous record holder, the Ford Model T. Beetle No. 15,007,034 broke the record on 17 February 1972. By 1973, total production was over 16 million, and by 23 June 1992, over 21 million had been produced.
The Beetle is arguably the world's best-selling car design. More units of the Toyota Corolla brand have been sold, but there have been many total redesigns of the Corolla, each amounting to a new car design with the same name.
[edit] Diesel
In 1951, Volkswagen prototyped a 1.3 litre diesel engine. Volkswagen made only 2 air-cooled boxer diesel engines that were not turbocharged, and installed one engine in a Type 1 and another in a Type 2. The diesel Beetle was time tested on the Nürburgring and achieved 0-100 km/h (0-60 mph) in 60 seconds.[15]
The third "VW 38" pre-series model produced
Rear, restored 1949 VW Beetle
VW Standard of 1950
Rear, restored 1961 VW Beetle with ragtop
Dashboard of a Mexican 1969 VW Beetle
Interior of a 1949 VW Beetle
VW 1303 Cabriolet
A VW 1303LS from Turkey (photo infrared)
Beetle 1968 restored (USA)
[edit] Introduction to the UK
The first Volkswagen Beetle in the UK was sold in June 1953, in Sheffield, by Jack Gilder. He had been fascinated by both the design and engineering of the Beetle when he came across one in Belgium during the war. He applied for the franchise as soon as the opportunity presented itself and became Volkswagen’s representative in the North of England.
[edit] VW Beetle 1967
1967 Volkswagen Beetle Engine(s) 1500 cc OHV H4, 40 kilowatts (54 hp) @ 4200 rpm, 105 N·m (77 lb·ft) @ 2600,
bore 83 mm,
stroke 69 mm,
comp ratio 7.5:1
Transmission(s) 4-speed manual
Wheelbase 2,400 mm (94.5 in)
Length 4,079 mm (160.6 in)
Width 1,539 mm (60.6 in)
The Volkswagen Beetle underwent significant changes for the 1967 model. While the car appeared similar to earlier models, much of the drivetrain was noticeably upgraded. Some of the changes to the Beetle included a bigger engine for the second year in a row. Horsepower had been increased to 37 kilowatts (50 hp) the previous year, and for 1967 it was increased even more, to 40 kilowatts (54 hp).
On US models, the output of the electrical generator was increased from 180 to 360 watts, and upgraded from a 6-volt to a 12-volt system. The clutch disc also increased in size, and changes were made to the flywheel, braking system, and rear axle. New standard equipment included two-speed windscreen wipers, reversing lights, a driver's armrest on the door, locking buttons on the doors, and a passenger's side exterior mirror.
In February 1967, inventor Don P. Dixon of San Antonio, Texas filed and was ultimately granted a patent for the first air conditioning unit specifically designed for the Beetle, which were soon offered by US dealerships.[16]
The 1967 model weighed 840 kg (1,852 lb), which was a typical weight for a European car at this time. Top speed was 130 km/h (81 mph).
For 1968, in accord with the newly-enacted U.S. Federal Motor Vehicle Safety Standard 108, the clear glass headlamp covers were deleted; the headlamps were brought forward to the leading edge of the front fenders, and the sealed-beam units were exposed and surrounded by chrome bezels. At the same time, Beetles sold outside North America received the same more upright and forward headlamp placement, but with replaceable-bulb headlamps compliant with ECE regulations rather than the U.S. sealed beams.
[edit] The Super Beetle and final evolution
VW 1303 (1973)
In 1971, while production of the "standard" Beetle continued, a Type 1 variant called the Super Beetle, produced from model year 1971 to 1979 (1302s from 1971 to 1972, and 1303s from 1973 onwards), offered MacPherson strut front suspension, which required a significant redesign of the front end. This resulted not only in a better turning radius (despite having a 20 mm (3/4 in) longer wheelbase), but because of the replacement of the bulky dual parallel torsion bar beams which had intruded upward into a large area within the trunk, and the stretched "nose" of the vehicle which permitted the relocation of the spare tire from a near vertical to a low horizontal position, this opened up approximately double the usable luggage space in the front compartment. Air pressure was used from the spare tire to pressurize the windshield washer canister, as an electric pump was not used to deploy windshield washer fluid for windshield cleaning.
1972 Super Beetles had a slightly larger rear window, larger front brakes, and four rows of vents (versus two rows previously) on the engine deck lid. The tail lights now incorporated reversing lights. The "four spoke" steering wheel and steering column were re-engineered to the "energy absorbing" design for better crash safety. A socket for the VW Dealer Diagnosis was fitted inside the engine compartment.
In 1973, the introduction of a more aerodynamically curved windscreen pushed it forward and away from the passengers, purportedly due to US Department of Transportation safety requirements. This allowed for a redesigned, "padded" dashboard (all pre-73 Beetles had virtually no horizontal dash area). A 2-speed heater fan, higher rear mudguards, and larger tail lights (nicknamed 'elephant's feet') were added. The changes to the heater/windshield wiper housing and curved windshield resulted in slight redesign of the front hood, making the 1971 and 1972 Super Beetle hoods unique.
For 1974 the previous flat steel bumper mounting brackets were replaced with tubular "self restoring energy absorbing" attachments, effectively shock absorbers for the bumpers. The steering knuckle and consequently the lower attach point of the strut was redesigned to improve handling and stability in the event of a tire blowout. This makes the struts from pre-74 Supers not interchangeable with 1974-79 makes.[17]
1975 brought the replacement of carburetors with Air Flow Control (AFC) Fuel Injection on U. S. and Canadian Beetles, a derivative of the more complex Bosch fuel injection system used in the Volkswagen Type III. The fuel injected engine also received a new muffler and the option of an upstream catalytic converter required on some models (e.g. California), necessitating a bulge in the rear apron sheet metal directly under the rear bumper, and replacing the distinctive dual "pea shooter" pipes with a single offset tailpipe, all of which make the fuel injected models easy to identify at a glance. Other changes were rack and pinion steering vs. the traditional worm and roller gearbox, and a larger license plate lamp housing below the engine lid. The front turn indicators were moved from the top of the fenders into the bumper bars on European models, a portend of the "Euro look" style years later by Beetle restorers.
In 1976, the hard top Super Beetle and 1300 were discontinued (though convertibles remained Super Beetles through 1979) and replaced with an 'improved' standard Beetle with 1600 cc engine, independent rear suspension, front disc brakes, blinkers in the front bumpers, elephant's foot tail lights and rubber inserts in the bumper bars. The "Auto-stick" transmission was dropped. 1976-on Super Beetles saw no significant engineering changes, only a few cosmetic touches and new paint options, including the "Champagne Edition" models (white on white was one example) to the final 1979 "Epilogue Edition" black on black, in salute to the first Beetles produced in the 1930s.
[edit] The Beetle Cabriolet
The Beetle Cabriolet began production in 1949 by Karmann in Osnabrück. It was in 1948 when Wilhelm Karmann bought a VW Beetle limousine and converted it into a four-seated convertible. After successfully presentating at VW in Wolfsburg, production started in 1949. After a number of stylistic and technical alterations made to the Karmann Cabriolet (corresponding to the many changes VW made to the Beetle throughout its history), the last of 331,847 cabriolets came off the conveyor belt on 10 January 1980.
[edit] Decline
VW 1300 (1972) with an aftermarket rain shield over the engine hatch air vents.
Though extremely successful in the 1960s, the Beetle was faced with stiff competition from more modern designs. The Japanese had refined rear-wheel-drive, water-cooled, front-engine small cars to where they sold well in the North American market, and Americans introduced their own similarly sized rear-wheel-drive Chevrolet Vega, Ford Pinto and AMC Gremlin in the 1970s. The superminis in Europe adopted even more efficient transverse-engine front-wheel-drive layouts, and sales began dropping off in the mid 1970s. There had been several unsuccessful attempts to replace or supplement the Beetle in the VW product line throughout the 1960s; the Type 3, Type 4, and the NSU-based K70 were all less successful than the Beetle, though aimed at more upscale markets for which VW lacked credibility. The over-reliance on the Beetle meant that Volkswagen was in financial crisis by 1974. It needed German government funding to produce the Beetle's replacement. Only when production lines at Wolfsburg switched to the new watercooled, front-engined, front-wheel drive Golf designed by Giorgetto Giugiaro in 1974, (sold in North America as the "Rabbit") did Volkswagen produce a car as successful as the Beetle. The Golf would be periodically redesigned over its lifetime with only a few components carried over between models, while the Beetle used only minor refinements of its original design.
The Golf did not kill Beetle production, which continued in smaller numbers at other German factories until 19 January 1978, when mainstream production shifted to Brazil and Mexico, markets where low operating cost was more important. It is important to note that the Beetle Cabriolet was still produced for the North American market in Germany until 10 January 1980. The last Beetle was produced in Puebla, Mexico, in July 2003.[2] The final batch of 3,000 Beetles were sold as 2004 models and badged as the Última Edición, with whitewall tires, a host of previously-discontinued chrome trim, and the choice of two special paint colors taken from the New Beetle. Production in Brazil ended in 1986, then started again in 1993 and continued until 1996. Volkswagen sold Beetle sedans in the United States until August 1977 (the Beetle convertible a.k.a. Cabriolet was sold until January 1980) and in Europe until 1985, with private companies continuing to import cars produced in Mexico even after production of the Beetle had ended.
The Beetle outlasted most other automobiles which had copied the rear air-cooled engine layout such as those by Subaru, Fiat, Renault and General Motors. Porsche's sport coupes which were originally based on Volkswagen parts and platforms continue to use the classic rear engine layout (but water-cooled and moved forwards) in the Porsche 911 series, which remains competitive in the 2000s.
[edit] The Beetle in other countries
Other countries produced Beetles from CKD (complete knockdown kits): Ireland, Thailand, Indonesia, South Africa, Australia, and Nigeria have assembled Beetles under license from VW.[18]
Beetles produced in Mexico and Brazil had several differences:
* Brazilian production started in 1950, with parts imported from Germany. In 1959 the cars were 100% made in Brazil. The car was made until 1986. In 1993 production started again but only continued till 1996. The Brazilian version retained the 1958-1964 body style (Europe and U.S. version) with the thick door pillars and small quarter glass; this body style was also produced in Mexico until 1971. Around 1973, Brazilian Beetles were updated with the 1968+ sheetmetal, bumpers, and 4-lug rims; although the 5-stud rims and "bugeye" headlights were produced as late as 1972 (the base VW 1200 was similar to the 1964 European/U.S. 1200). Brazilian CKD kits (complete knock down) were shipped to Nigeria between 1975-1987 where Beetles were locally produced. The Brazilian-produced versions have been sold in neighboring South American nations bordering Brazil, including Argentina and Peru.
* In Brazil, the beetle is called "Fusca".
* The Brazilian VW Bug have four different sized engines: 1200 cc, 1300 cc, 1500 cc, and, finally, 1600 cc. In the 1970s, Volkswagen made the SP-2 (derived from the VW Beetle chassis and powertrain) that used an air-cooled 1700 cc VW engine that was a regular 1600 cc engine with its engine displacement increased by the usage of large diameter cylinders. In Brazil the VW Bug never received electronic fuel injection (the air-cooled flat four engine from the Beetle received this, but to equip solely the VW Kombi later models), but, instead, retained single or double-single carburetion throughout its entire life, although the carburetion specs differs from engines of different years and specs.
* The production of the air-cooled engine finally ended in 2006, after more than 60 years. It was last used in the Brazilian version of the VW Bus, called the "Kombi", and was replaced by a 1.4-liter water-cooled engine with a front-mounted cooling system.
1996 Mexican Volkswagen Beetle. The last one with chrome moldings.
2003 Mexican Volkswagen Beetle.
[edit] Beetles in Mexico
Main article: Volkswagen Beetle in Mexico
Mexican production began in 1955 due to agreements with companies such as Chrysler in Mexico and Studebaker-Packard Company which ensambled cars imported in CKD form. From since 1964 they are locally produced. They have the larger windshield, rear window, door and quarter glass between from 1971; and the rear window from the 1965-71 German built models was used on the Mexican models from 1972 to 1985, when it was replaced with the larger rear window used on 1972 and later German built Beetles. This version, after the mid-1970s, saw little change with the incorporation of electronic ignition in 1988, an anti-theft alarm system in 1990, a catalytic converter in 1991 (by law requirement), as well as electronic fuel injection, hydraulic valve lifters, and a spin-on oil filter in 1993. The front turn signals were located in the bumper instead of the Beetle's traditional placement on top of the front fenders from the 1977 model year on, as they had been on German Beetles sold in Europe of the same time period. From the 1995, the Mexican Beetle includes front disc brakes and front automatic seat belts, and from the 1996 model, the chrome moldings disappear leaving body colored bumpers and black moldings instead. In mid 1996, front drum brakes and fixed front seat belts are re-launched in a new budget version called the "Volkswagen Sedán City", which is sold alongside with the upscale version "Volkswagen Sedán Clásico" which features front disc brakes, automatic seat belts, right side mirror, velour upholstery, optional metallic colors and wheel covers in matte finish, which can be also found in some 1980's Beetles and Buses. These two versions were sold until 1999. From late 1999 to 2003, The Sedán Clásico was discontinued and the Sedán City loses its prefix and becomes the disc brakes, automatic seat belts and optional metallic colors. This last version is named the "Volkswagen Sedán Unificado" or simply the "Volkswagen Sedán".
Independent importers continued to supply several major countries, including Germany, France, and the UK until the end of production in 2003. Devoted fans of the car even discovered a way to circumvent United States safety regulations by placing more recently manufactured Mexican Beetles on the floorpans of earlier, US-registered cars. The Mexican Beetle (along with its Brazilian counterpart) was on the US DOT's (Department of Transportation) hot list of gray market imports after 1978 as the vehicle did not meet safety regulations.
In the Southwest United States (Arizona, California, New Mexico, Texas), Mexican Beetles (and some Brazilian T2c Transporters) are a fairly common sight since Mexican nationals can legally operate the vehicle in the United States, provided the cars remain registered in Mexico.
The end of production in Mexico can be attributed primarily to Mexican political measures: the Beetles no longer met emissions standards for Mexico City, in which the ubiquitous Beetles were used as taxicabs; and the government outlawed their use as taxicabs because of rising crime rates, requiring only four-door vehicles be used. In addition, Volkswagen (now Germany's largest automaker) has been attempting to cultivate a more upscale, premium brand image, and the humble Beetle, with its US$7000 base price, clashed with this identity, as seen in the Touareg and Passat luxury vehicles.In the late 1990s consumers strongly preferred more modern cars such as the Mexican Chevy, the Nissan Tsuru, and the Volkswagen Pointer and Lupo.
[edit] Beetles In Australia
Official importation of the Volkswagen Beetle into Australia began in 1953 with local assembly operations commencing the following year. Volkswagen Australia was formed in 1957 and by 1960 locally produced panels were being used for the first time. Australian content had reached almost 95% by 1967 however declining sales saw the company revert to using imported components the following year. In 1976 Volkswagen ceased Australian assembly operations, their factory in Clayton, Victoria was sold to Nissan Australia and all Volkswagens were once again fully imported. [19]
Many Australian or "Australasian" Beetles had accessories or modifications made for the Australian road[citation needed].
There was also an Australian-built vehicle based on the Type 1 known as the Volkswagen Country Buggy as well as a coupe similar to the Karmann Ghia based on the Beetle called the Ascort.
[edit] Beetle in a Bush War
Bizarrely, the volkswagen chassis was used as the basis for an anti-mine APC called the Leopard security vehicle, which was fielded by Rhodesia during the Rhodesian Bush War
[edit] Beetle customization
See also: Dune buggy and Baja Bug
Baja Bug-style modified Beetle
The Beetle is popular with customizers throughout the world, not only because it is cheap and easy to work on, but because its iconic looks can be personalised and the flat four motor is so tunable. Its very ubiquity makes even subtle changes noticeable.
[edit] Exterior
There are many popular Beetle styles, from a 'Cal Looker' to a Rat rod. They vary between themselves, but are very similar in many ways. Also, the California Look has changed during the 30+ years of its lifespan. The most typical way to customise the exterior is to change the wheels and lower the suspension of the car. The favorite wheels are period-style EMPI 5- or 8-spokes, Speedwell BRMs, or Porsche factory rims like Fuchs from the classic 911. One of the original California Look modifications is to replace or remove the bumpers and trim, either to give a cleaner look or to reduce the curb weight; if bumpers are removed, pushbars are common. The stock bumpers are usually chromed or polished, sometimes painted or powder coated. There are many clubs dedicated to 'Cal Look', including the DKP ('Der Kleiner Panzers', or in English, 'The little Tanks') in the USA, which was one of the first clubs dedicated to true 'Cal Look' cars. There are also currently many big 'Cal Look' VW clubs based in Europe, including the DAS (Das Autobahn Scrapers) in Belgium, the DFL (Der Fieser Luftkühlers) in Germany and the JG54 Grünherz (Greenhearts) in the UK.
For a 'Resto Cal' look, a roof rack and similar accessories can be added. There are many other aftermarket parts that can be added to the Beetle, including wing mirrors, chrome wipers, stone guards, mud flaps, and badges. Rear light and front indicator lenses can also be changed.
VW Beetle modified in 70s California Look style
For a more custom look, smoothing and shaving the body (removing trim and other parts) is done, including door handles, badges and driprails, and replacing taillights and front indicators with smaller, simpler units. Frenching (tunnelling) headlights, frequent in non-VW customs and rods, is not common, but dramatic lowering is, and unusual hood and trunk hinging are commonplace. Another exterior modification that is seen occasionally is for the roof to be chopped and lowered just like other non beetle hot rods and customs, giving a meaner, lower and sleeker appearance.
violet 1966 beetle
[edit] Interior
Many Beetle owners try to keep their Beetle interior stock. Others will fit a sound system, which usually consists of a head unit and possibly some speakers and a subwoofer (usually mounted in the front of the car). Aftermarket steering wheels can be added along with auxiliary gauges. For a true race look, the interior can be stripped and a full roll cage installed, along with bucket seats and race harnesses although bucket seating is already the default seating for a Beetle.
The VW Type 1 chassis, being easily separated from its original body without removal of engine, transmission, or suspension, has provided the basis for countless custom re-bodyings, usually of fiberglass and usually replicating other, less humble vehicles. Mercedes, MG and Porsche replicas are among the popular choices. The more successful being the Sterling sports car in the 70's Fiberglass body kits with its all original body styling. These "kit cars", although derided by many for their lack of authenticity, provide to their owners a much cheaper, often more-reliable means of enjoying a dream vehicle.
[edit] Power
Volvo B18/B20 engine fitted to VW Beetle for racing.
Because most parts of the flat-4 engine other than the crankcase are bolted on, they are easily exchanged with larger or more high-performance items. The standard VW engine has been modified from 1600 cc (the largest factory-produced Type 1 engine) to configurations well over 2400 cc using larger piston/cylinder kits, turbochargers, and other performance-enhancing parts. A variety of other powerplants, including the VW Type 4 (also used in the 914) 2-liter flat four, Chevy Corvair and Porsche 911 flat sixes have been used. Even the turbocharged flat 4s from Subaru or Alfa Romeo have been used as well. Kits for installing Rover V8 engines have also been available. These variants tend to be mated to the stronger Type 2 (Bus, Combi) transmission. Dual carb setups are very common on Beetles (especially the 1600 cc dual port engine) as well as EFI. Also a wide range of exhaust systems are available. 4-into-1 headers are very popular, and are often used with a stinger, glasspack, or more modern "quiet pack" mufflers. The world record for fastest and quickest four cylinder 1/4 mile drag vehicle is held by a type 1 based engine built and maintained by vwparadise of San Marcos California. Its official run is 6.60 @ 203.94 mph quarter-mile although unofficially the quickest & fastest has been a 6.53 at 209.98 mph.[20]
Advertisement from c.1939 says "Five marks a week you must put aside - If in your own car you want to ride!")
Starting in 1931, Ferdinand Porsche and Zündapp developed the "Auto für Jedermann" (car for everybody). Porsche already preferred the flat-4 cylinder engine, but Zündapp used a water-cooled 5-cylinder radial engine. In 1932, three prototypes were running.[4] All of those cars were lost during the war, the last in a bombing raid over Stuttgart in 1945.
Porsche Type 12, 1931/32 by Zündapp Nürnberg
In 1933, Adolf Hitler gave the order to Ferdinand Porsche to develop a "Volks-Wagen" . The concept may have been influenced by an earlier design of the same name, created by Josef Ganz, a Jewish engineer who had designed a "Volks-Wagen" in the 1920s.[5] The name means "people's car" in German, in which it is pronounced [ˈfolksvɑːgən]). Hitler required a basic vehicle capable of transporting two adults and three children at 100 km/h (62 mph). The "People's Car" would be available to citizens of the Third Reich through a savings scheme at 990 Reichsmark, about the price of a small motorcycle (an average income being around 32RM a week).[6]
Erwin Komenda, Porsche's chief designer, was responsible for the design and style of the car. But production only became worthwhile when finance was backed by the Third Reich. War started before large-scale production of the Volkswagen started, and manufacturing shifted to producing military vehicles. Production of civilian VW automobiles did not start until post-war occupation.
[edit] The military Beetle and production up to 1945
Kommandeurwagen
Initially called the Porsche 60 by Ferdinand Porsche, it was officially named the KdF-Wagen when the project was launched. The name refers to Kraft durch Freude (Strength Through Joy), the official leisure organization in the Third Reich. It was later known as the Type 1, but became more commonly known as the Beetle after World War II.
Prototypes appeared from 1931; the first were produced by Zündapp in Nürnberg, the Porsche Type 12. The next prototype series (Porsche Type 32) were built in 1933 by NSU, another motorcycle company. When Chrysler brought out its DeSoto Airflow coupe in 1934, final design for the car was decided.
In October 1935 the first Type 60 was ready. In 1935 testing of the "V3" started. The "VW30" prototypes had further testing in 1937. All cars already had the distinctive round shape and the air-cooled, rear-mounted engine, except for the Type 12, Zündapp preferred a 5-cylinder radial watercooled engine.
The factory had only produced a handful of cars by start of the war in 1939. Consequently, the first volume-produced versions of the car's chassis were military vehicles, the Kübelwagen Type 82 (approx. 52,000 built) and the amphibious Schwimmwagen Type 166 (approx. 14,000 built).
The car was designed to be as simple as possible mechanically, so that there was less to go wrong; the aircooled 985 cc 25 horsepower (19 kW) motors proved especially effective in actions of the German Afrika Korps in Africa's desert heat. This was due to the built-in oil-cooler, and the superior performance of the flat-4 engine configuration. The innovative suspension design used compact torsion bars instead of coil or leaf springs. The Beetle is more or less airtight and will float on water, indeed it is hard to slam the door on one since the difference in air pressure pushes it back before it shuts.
The model village of Stadt des KdF-Wagens was created in Lower Saxony in 1938 for the benefit of the workers at the factory.
A handful of Beetles were produced specifically for civilians, primarily for the Nazi elite, in the years 1940–1945, but production figures were small. Because of gasoline shortages, a few wartime "Holzbrenner" Beetles were fueled by wood pyrolysis gas producers under the hood. In addition to the Kübelwagen, Schwimmwagen, and handful of others, the factory managed another wartime vehicle: the Kommandeurwagen; a Beetle body mounted on the Kübelwagen chassis.
669 Kommandeurwagens were produced up to 1945, when all production was halted because of heavy damage to the factory by Allied air raids. Much of the essential equipment had already been moved to underground bunkers for protection, which let production resume quickly after hostilities ended.
[edit] Conflict with Tatra
Much of the Beetle’s design was inspired by the advanced Czech Tatra cars, designed under chief engineer Hans Ledwinka. In particular, Tatra’s T97 and T77a models show striking similarities with the later Volkswagen from many angles.
Thirties Tatras used streamlined bodies with rear-mounted engines. The T97,[7] which is widely held to be the closest Tatra model to Porsche’s Volkswagen, had a four-cylinder horizontally-opposed (‘flat four’) air-cooled engine. On a smaller scale, the company’s V570, a prototype for a smaller car, also shows quite a resemblance to the later German car.
But it wasn’t just Tatra’s aerodynamic styling that influenced Porsche. Tatra had pioneered the use of air-cooling in road vehicle engines with the original T77 in 1934. Air-cooling was demanding technologically, but desirable: there was no anti-freeze in the 1930s, so a vehicle could not be left parked for long in cold weather with its coolant in situ. Tatra’s wealthy customers could afford to pay for advanced technology, but Ferdinand Porsche was out on a limb in specifying air-cooling for his people’s car. In the end, it was subsidies from the Nazi government that paid for Porsche’s engineering good taste and brought the convenience of air-cooling to a mass audience — albeit only after the second world war.
According to the book Car Wars, Adolf Hitler called the Tatra 'the kind of car I want for my highways'.[8] In the same book, it is said that Ferdinand Porsche admitted ‘to have looked over Ledwinka’s shoulder’ while designing the Volkswagen.[8] Tatra launched a lawsuit, but this was stopped when Germany invaded Czechoslovakia. At the same time, Tatra was forced to stop producing the T97. The matter was re-opened after WW2 and in 1961 Volkswagen paid Tatra 3,000,000 Deutsche Marks in compensation. These damages meant that Volkswagen had little money for the development of new models and the Beetle's production life was necessarily extended. Tatra ceased producing passenger cars in 1950, then resumed again in 1954 as a manufacturer of large luxurious cars and limousines under various Communist governments in Czechoslovakia. Even the company’s last limousines were rear-engined and air cooled.
Tatra is now a truck manufacturer. All its engines are still air-cooled, despite the demands of modern emissions regulations.
[edit] Post-war production and boom
In occupied Germany, the Allies followed the Morgenthau plan to remove all German war potential by complete or partial pastoralization. As part of this, in the Industrial plans for Germany, the rules for which industry Germany was to be allowed to retain were set out. German car production was set at a maximum of 10% of the 1936 car production numbers.[9]
The Volkswagen factory at Wolfsburg was handed over by the Americans to British control in 1945; it was to be dismantled and shipped to Britain.[10] Thankfully for Volkswagen, no British car manufacturer was interested in the factory; "the vehicle does not meet the fundamental technical requirement of a motor-car ... it is quite unattractive to the average buyer ... To build the car commercially would be a completely uneconomic enterprise."[10] The factory survived by producing cars for the British Army instead.[10] Allied dismantling policy changed in late 1946 to mid 1947, although heavy industry continued to be dismantled until 1951. In March 1947 Herbert Hoover helped change policy by stating
"There is the illusion that the New Germany left after the annexations can be reduced to a 'pastoral state'. It cannot be done unless we exterminate or move 25,000,000 people out of it."[11]
The re-opening of the factory is largely accredited to British Army officer Major Ivan Hirst (1916–2000).[12] Hirst was ordered to take control of the heavily bombed factory, which the Americans had captured. His first task was to remove an unexploded bomb which had fallen through the roof and lodged itself between some pieces of irreplaceable production equipment; if the bomb had exploded, the Beetle's fate would have been sealed. Hirst persuaded the British military to order 20,000 of the cars,[6] and by 1946 the factory was producing 1,000 cars a month. During this period the car and its town changed their Nazi-era names to Volkswagen (people's car) and Wolfsburg, respectively. The first 1,785 Beetles were made in a factory near Wolfsburg in 1945.
The jeweled one-millionth VW Beetle
Following the Army-led restart of production,former Opel manager (and formerly a detractor of the VW*) Heinz Nordhoff was appointed director of the Volkswagen factory,[6] under whom production increased dramatically over the following decade, with the one-millionth car coming off the assembly line by 1955. During this Post-war period, the Beetle had superior performance in its category with a top speed of 115 km/h (71 mph) and 0-100 km/h (0-60 mph) in 27.5 seconds on 36 mpg (15 km/l) for the standard 25 kw (33 hp) engine. This was far superior to the Citroën 2CV and Morris Minor, and even competitive with more modern small cars like the Mini of the 1960s and later.
* According to the book Small Wonder by Walter Henry Nelson:
"The engine fires up immediately without a choke. It has tolerable road-handling and is economical to maintain. Although a small car, the engine has great elasticity and gave the feeling of better output than its small nominal size."
But opinion in the United States was not flattering, perhaps because of the characteristic differences between the American and European car markets. Henry Ford II once described the car as 'a little box.'[citation needed] The Ford company was offered the entire VW works after the war for free. Ford's right-hand man Ernest Breech was asked what he thought, and told Henry II, "What we're being offered here, Mr. Ford, isn't worth a damn!" With that, the Ford Motor Company lost out on the chance to build the world's most popular car since his grandfather's own Model-T.
During the 1950s, the car was modified progressively: the obvious visual changes mostly concerned the windows.[13] In March 1953, the small oval two-piece rear window was replaced by a slightly larger single-piece window. More dramatically, in August 1957 a much larger full width rear window replaced the oval one. 1964 saw the introduction of a widened cover for the light over the rear licence plate. Towards the end of 1964, the height of the side windows and windscreen grew slightly, giving the cabin a less pinched look: this coincided with the introduction of a very slightly curved ("panoramic") windscreen, though the curve was barely noticeable. The same body appeared during 1966, with a 1300 cc engine in place of the 1200 cc engine: it was only in the 1973 model Super Beetle that the beetle acquired an obviously curved windscreen. The flat windscreen remained on the standard beetle.
There were also changes under the bonnet. In 1954, by adding 2mm to the bore, Volkswagen increased the engine capacity from 1,131 to 1,192.[14] This coincided with upgrades to various key components including a redesign of the crankshaft. The result was a power uplift from 33 bhp to a claimed 40 bhp and an improvement in the engine's free revving abilities without compromising the torque characteristics at lower engine speeds.[14] At the same time, compression ratios were progressively raised as, little by little, the octane ratings of available basic fuel was raised in major markets during the 1950s and 1960s.[14]
During the 1960s and early 1970s, advertising campaigns and a reputation for reliability and sturdiness helped production figures to surpass the levels of the previous record holder, the Ford Model T. Beetle No. 15,007,034 broke the record on 17 February 1972. By 1973, total production was over 16 million, and by 23 June 1992, over 21 million had been produced.
The Beetle is arguably the world's best-selling car design. More units of the Toyota Corolla brand have been sold, but there have been many total redesigns of the Corolla, each amounting to a new car design with the same name.
[edit] Diesel
In 1951, Volkswagen prototyped a 1.3 litre diesel engine. Volkswagen made only 2 air-cooled boxer diesel engines that were not turbocharged, and installed one engine in a Type 1 and another in a Type 2. The diesel Beetle was time tested on the Nürburgring and achieved 0-100 km/h (0-60 mph) in 60 seconds.[15]
The third "VW 38" pre-series model produced
Rear, restored 1949 VW Beetle
VW Standard of 1950
Rear, restored 1961 VW Beetle with ragtop
Dashboard of a Mexican 1969 VW Beetle
Interior of a 1949 VW Beetle
VW 1303 Cabriolet
A VW 1303LS from Turkey (photo infrared)
Beetle 1968 restored (USA)
[edit] Introduction to the UK
The first Volkswagen Beetle in the UK was sold in June 1953, in Sheffield, by Jack Gilder. He had been fascinated by both the design and engineering of the Beetle when he came across one in Belgium during the war. He applied for the franchise as soon as the opportunity presented itself and became Volkswagen’s representative in the North of England.
[edit] VW Beetle 1967
1967 Volkswagen Beetle Engine(s) 1500 cc OHV H4, 40 kilowatts (54 hp) @ 4200 rpm, 105 N·m (77 lb·ft) @ 2600,
bore 83 mm,
stroke 69 mm,
comp ratio 7.5:1
Transmission(s) 4-speed manual
Wheelbase 2,400 mm (94.5 in)
Length 4,079 mm (160.6 in)
Width 1,539 mm (60.6 in)
The Volkswagen Beetle underwent significant changes for the 1967 model. While the car appeared similar to earlier models, much of the drivetrain was noticeably upgraded. Some of the changes to the Beetle included a bigger engine for the second year in a row. Horsepower had been increased to 37 kilowatts (50 hp) the previous year, and for 1967 it was increased even more, to 40 kilowatts (54 hp).
On US models, the output of the electrical generator was increased from 180 to 360 watts, and upgraded from a 6-volt to a 12-volt system. The clutch disc also increased in size, and changes were made to the flywheel, braking system, and rear axle. New standard equipment included two-speed windscreen wipers, reversing lights, a driver's armrest on the door, locking buttons on the doors, and a passenger's side exterior mirror.
In February 1967, inventor Don P. Dixon of San Antonio, Texas filed and was ultimately granted a patent for the first air conditioning unit specifically designed for the Beetle, which were soon offered by US dealerships.[16]
The 1967 model weighed 840 kg (1,852 lb), which was a typical weight for a European car at this time. Top speed was 130 km/h (81 mph).
For 1968, in accord with the newly-enacted U.S. Federal Motor Vehicle Safety Standard 108, the clear glass headlamp covers were deleted; the headlamps were brought forward to the leading edge of the front fenders, and the sealed-beam units were exposed and surrounded by chrome bezels. At the same time, Beetles sold outside North America received the same more upright and forward headlamp placement, but with replaceable-bulb headlamps compliant with ECE regulations rather than the U.S. sealed beams.
[edit] The Super Beetle and final evolution
VW 1303 (1973)
In 1971, while production of the "standard" Beetle continued, a Type 1 variant called the Super Beetle, produced from model year 1971 to 1979 (1302s from 1971 to 1972, and 1303s from 1973 onwards), offered MacPherson strut front suspension, which required a significant redesign of the front end. This resulted not only in a better turning radius (despite having a 20 mm (3/4 in) longer wheelbase), but because of the replacement of the bulky dual parallel torsion bar beams which had intruded upward into a large area within the trunk, and the stretched "nose" of the vehicle which permitted the relocation of the spare tire from a near vertical to a low horizontal position, this opened up approximately double the usable luggage space in the front compartment. Air pressure was used from the spare tire to pressurize the windshield washer canister, as an electric pump was not used to deploy windshield washer fluid for windshield cleaning.
1972 Super Beetles had a slightly larger rear window, larger front brakes, and four rows of vents (versus two rows previously) on the engine deck lid. The tail lights now incorporated reversing lights. The "four spoke" steering wheel and steering column were re-engineered to the "energy absorbing" design for better crash safety. A socket for the VW Dealer Diagnosis was fitted inside the engine compartment.
In 1973, the introduction of a more aerodynamically curved windscreen pushed it forward and away from the passengers, purportedly due to US Department of Transportation safety requirements. This allowed for a redesigned, "padded" dashboard (all pre-73 Beetles had virtually no horizontal dash area). A 2-speed heater fan, higher rear mudguards, and larger tail lights (nicknamed 'elephant's feet') were added. The changes to the heater/windshield wiper housing and curved windshield resulted in slight redesign of the front hood, making the 1971 and 1972 Super Beetle hoods unique.
For 1974 the previous flat steel bumper mounting brackets were replaced with tubular "self restoring energy absorbing" attachments, effectively shock absorbers for the bumpers. The steering knuckle and consequently the lower attach point of the strut was redesigned to improve handling and stability in the event of a tire blowout. This makes the struts from pre-74 Supers not interchangeable with 1974-79 makes.[17]
1975 brought the replacement of carburetors with Air Flow Control (AFC) Fuel Injection on U. S. and Canadian Beetles, a derivative of the more complex Bosch fuel injection system used in the Volkswagen Type III. The fuel injected engine also received a new muffler and the option of an upstream catalytic converter required on some models (e.g. California), necessitating a bulge in the rear apron sheet metal directly under the rear bumper, and replacing the distinctive dual "pea shooter" pipes with a single offset tailpipe, all of which make the fuel injected models easy to identify at a glance. Other changes were rack and pinion steering vs. the traditional worm and roller gearbox, and a larger license plate lamp housing below the engine lid. The front turn indicators were moved from the top of the fenders into the bumper bars on European models, a portend of the "Euro look" style years later by Beetle restorers.
In 1976, the hard top Super Beetle and 1300 were discontinued (though convertibles remained Super Beetles through 1979) and replaced with an 'improved' standard Beetle with 1600 cc engine, independent rear suspension, front disc brakes, blinkers in the front bumpers, elephant's foot tail lights and rubber inserts in the bumper bars. The "Auto-stick" transmission was dropped. 1976-on Super Beetles saw no significant engineering changes, only a few cosmetic touches and new paint options, including the "Champagne Edition" models (white on white was one example) to the final 1979 "Epilogue Edition" black on black, in salute to the first Beetles produced in the 1930s.
[edit] The Beetle Cabriolet
The Beetle Cabriolet began production in 1949 by Karmann in Osnabrück. It was in 1948 when Wilhelm Karmann bought a VW Beetle limousine and converted it into a four-seated convertible. After successfully presentating at VW in Wolfsburg, production started in 1949. After a number of stylistic and technical alterations made to the Karmann Cabriolet (corresponding to the many changes VW made to the Beetle throughout its history), the last of 331,847 cabriolets came off the conveyor belt on 10 January 1980.
[edit] Decline
VW 1300 (1972) with an aftermarket rain shield over the engine hatch air vents.
Though extremely successful in the 1960s, the Beetle was faced with stiff competition from more modern designs. The Japanese had refined rear-wheel-drive, water-cooled, front-engine small cars to where they sold well in the North American market, and Americans introduced their own similarly sized rear-wheel-drive Chevrolet Vega, Ford Pinto and AMC Gremlin in the 1970s. The superminis in Europe adopted even more efficient transverse-engine front-wheel-drive layouts, and sales began dropping off in the mid 1970s. There had been several unsuccessful attempts to replace or supplement the Beetle in the VW product line throughout the 1960s; the Type 3, Type 4, and the NSU-based K70 were all less successful than the Beetle, though aimed at more upscale markets for which VW lacked credibility. The over-reliance on the Beetle meant that Volkswagen was in financial crisis by 1974. It needed German government funding to produce the Beetle's replacement. Only when production lines at Wolfsburg switched to the new watercooled, front-engined, front-wheel drive Golf designed by Giorgetto Giugiaro in 1974, (sold in North America as the "Rabbit") did Volkswagen produce a car as successful as the Beetle. The Golf would be periodically redesigned over its lifetime with only a few components carried over between models, while the Beetle used only minor refinements of its original design.
The Golf did not kill Beetle production, which continued in smaller numbers at other German factories until 19 January 1978, when mainstream production shifted to Brazil and Mexico, markets where low operating cost was more important. It is important to note that the Beetle Cabriolet was still produced for the North American market in Germany until 10 January 1980. The last Beetle was produced in Puebla, Mexico, in July 2003.[2] The final batch of 3,000 Beetles were sold as 2004 models and badged as the Última Edición, with whitewall tires, a host of previously-discontinued chrome trim, and the choice of two special paint colors taken from the New Beetle. Production in Brazil ended in 1986, then started again in 1993 and continued until 1996. Volkswagen sold Beetle sedans in the United States until August 1977 (the Beetle convertible a.k.a. Cabriolet was sold until January 1980) and in Europe until 1985, with private companies continuing to import cars produced in Mexico even after production of the Beetle had ended.
The Beetle outlasted most other automobiles which had copied the rear air-cooled engine layout such as those by Subaru, Fiat, Renault and General Motors. Porsche's sport coupes which were originally based on Volkswagen parts and platforms continue to use the classic rear engine layout (but water-cooled and moved forwards) in the Porsche 911 series, which remains competitive in the 2000s.
[edit] The Beetle in other countries
Other countries produced Beetles from CKD (complete knockdown kits): Ireland, Thailand, Indonesia, South Africa, Australia, and Nigeria have assembled Beetles under license from VW.[18]
Beetles produced in Mexico and Brazil had several differences:
* Brazilian production started in 1950, with parts imported from Germany. In 1959 the cars were 100% made in Brazil. The car was made until 1986. In 1993 production started again but only continued till 1996. The Brazilian version retained the 1958-1964 body style (Europe and U.S. version) with the thick door pillars and small quarter glass; this body style was also produced in Mexico until 1971. Around 1973, Brazilian Beetles were updated with the 1968+ sheetmetal, bumpers, and 4-lug rims; although the 5-stud rims and "bugeye" headlights were produced as late as 1972 (the base VW 1200 was similar to the 1964 European/U.S. 1200). Brazilian CKD kits (complete knock down) were shipped to Nigeria between 1975-1987 where Beetles were locally produced. The Brazilian-produced versions have been sold in neighboring South American nations bordering Brazil, including Argentina and Peru.
* In Brazil, the beetle is called "Fusca".
* The Brazilian VW Bug have four different sized engines: 1200 cc, 1300 cc, 1500 cc, and, finally, 1600 cc. In the 1970s, Volkswagen made the SP-2 (derived from the VW Beetle chassis and powertrain) that used an air-cooled 1700 cc VW engine that was a regular 1600 cc engine with its engine displacement increased by the usage of large diameter cylinders. In Brazil the VW Bug never received electronic fuel injection (the air-cooled flat four engine from the Beetle received this, but to equip solely the VW Kombi later models), but, instead, retained single or double-single carburetion throughout its entire life, although the carburetion specs differs from engines of different years and specs.
* The production of the air-cooled engine finally ended in 2006, after more than 60 years. It was last used in the Brazilian version of the VW Bus, called the "Kombi", and was replaced by a 1.4-liter water-cooled engine with a front-mounted cooling system.
1996 Mexican Volkswagen Beetle. The last one with chrome moldings.
2003 Mexican Volkswagen Beetle.
[edit] Beetles in Mexico
Main article: Volkswagen Beetle in Mexico
Mexican production began in 1955 due to agreements with companies such as Chrysler in Mexico and Studebaker-Packard Company which ensambled cars imported in CKD form. From since 1964 they are locally produced. They have the larger windshield, rear window, door and quarter glass between from 1971; and the rear window from the 1965-71 German built models was used on the Mexican models from 1972 to 1985, when it was replaced with the larger rear window used on 1972 and later German built Beetles. This version, after the mid-1970s, saw little change with the incorporation of electronic ignition in 1988, an anti-theft alarm system in 1990, a catalytic converter in 1991 (by law requirement), as well as electronic fuel injection, hydraulic valve lifters, and a spin-on oil filter in 1993. The front turn signals were located in the bumper instead of the Beetle's traditional placement on top of the front fenders from the 1977 model year on, as they had been on German Beetles sold in Europe of the same time period. From the 1995, the Mexican Beetle includes front disc brakes and front automatic seat belts, and from the 1996 model, the chrome moldings disappear leaving body colored bumpers and black moldings instead. In mid 1996, front drum brakes and fixed front seat belts are re-launched in a new budget version called the "Volkswagen Sedán City", which is sold alongside with the upscale version "Volkswagen Sedán Clásico" which features front disc brakes, automatic seat belts, right side mirror, velour upholstery, optional metallic colors and wheel covers in matte finish, which can be also found in some 1980's Beetles and Buses. These two versions were sold until 1999. From late 1999 to 2003, The Sedán Clásico was discontinued and the Sedán City loses its prefix and becomes the disc brakes, automatic seat belts and optional metallic colors. This last version is named the "Volkswagen Sedán Unificado" or simply the "Volkswagen Sedán".
Independent importers continued to supply several major countries, including Germany, France, and the UK until the end of production in 2003. Devoted fans of the car even discovered a way to circumvent United States safety regulations by placing more recently manufactured Mexican Beetles on the floorpans of earlier, US-registered cars. The Mexican Beetle (along with its Brazilian counterpart) was on the US DOT's (Department of Transportation) hot list of gray market imports after 1978 as the vehicle did not meet safety regulations.
In the Southwest United States (Arizona, California, New Mexico, Texas), Mexican Beetles (and some Brazilian T2c Transporters) are a fairly common sight since Mexican nationals can legally operate the vehicle in the United States, provided the cars remain registered in Mexico.
The end of production in Mexico can be attributed primarily to Mexican political measures: the Beetles no longer met emissions standards for Mexico City, in which the ubiquitous Beetles were used as taxicabs; and the government outlawed their use as taxicabs because of rising crime rates, requiring only four-door vehicles be used. In addition, Volkswagen (now Germany's largest automaker) has been attempting to cultivate a more upscale, premium brand image, and the humble Beetle, with its US$7000 base price, clashed with this identity, as seen in the Touareg and Passat luxury vehicles.In the late 1990s consumers strongly preferred more modern cars such as the Mexican Chevy, the Nissan Tsuru, and the Volkswagen Pointer and Lupo.
[edit] Beetles In Australia
Official importation of the Volkswagen Beetle into Australia began in 1953 with local assembly operations commencing the following year. Volkswagen Australia was formed in 1957 and by 1960 locally produced panels were being used for the first time. Australian content had reached almost 95% by 1967 however declining sales saw the company revert to using imported components the following year. In 1976 Volkswagen ceased Australian assembly operations, their factory in Clayton, Victoria was sold to Nissan Australia and all Volkswagens were once again fully imported. [19]
Many Australian or "Australasian" Beetles had accessories or modifications made for the Australian road[citation needed].
There was also an Australian-built vehicle based on the Type 1 known as the Volkswagen Country Buggy as well as a coupe similar to the Karmann Ghia based on the Beetle called the Ascort.
[edit] Beetle in a Bush War
Bizarrely, the volkswagen chassis was used as the basis for an anti-mine APC called the Leopard security vehicle, which was fielded by Rhodesia during the Rhodesian Bush War
[edit] Beetle customization
See also: Dune buggy and Baja Bug
Baja Bug-style modified Beetle
The Beetle is popular with customizers throughout the world, not only because it is cheap and easy to work on, but because its iconic looks can be personalised and the flat four motor is so tunable. Its very ubiquity makes even subtle changes noticeable.
[edit] Exterior
There are many popular Beetle styles, from a 'Cal Looker' to a Rat rod. They vary between themselves, but are very similar in many ways. Also, the California Look has changed during the 30+ years of its lifespan. The most typical way to customise the exterior is to change the wheels and lower the suspension of the car. The favorite wheels are period-style EMPI 5- or 8-spokes, Speedwell BRMs, or Porsche factory rims like Fuchs from the classic 911. One of the original California Look modifications is to replace or remove the bumpers and trim, either to give a cleaner look or to reduce the curb weight; if bumpers are removed, pushbars are common. The stock bumpers are usually chromed or polished, sometimes painted or powder coated. There are many clubs dedicated to 'Cal Look', including the DKP ('Der Kleiner Panzers', or in English, 'The little Tanks') in the USA, which was one of the first clubs dedicated to true 'Cal Look' cars. There are also currently many big 'Cal Look' VW clubs based in Europe, including the DAS (Das Autobahn Scrapers) in Belgium, the DFL (Der Fieser Luftkühlers) in Germany and the JG54 Grünherz (Greenhearts) in the UK.
For a 'Resto Cal' look, a roof rack and similar accessories can be added. There are many other aftermarket parts that can be added to the Beetle, including wing mirrors, chrome wipers, stone guards, mud flaps, and badges. Rear light and front indicator lenses can also be changed.
VW Beetle modified in 70s California Look style
For a more custom look, smoothing and shaving the body (removing trim and other parts) is done, including door handles, badges and driprails, and replacing taillights and front indicators with smaller, simpler units. Frenching (tunnelling) headlights, frequent in non-VW customs and rods, is not common, but dramatic lowering is, and unusual hood and trunk hinging are commonplace. Another exterior modification that is seen occasionally is for the roof to be chopped and lowered just like other non beetle hot rods and customs, giving a meaner, lower and sleeker appearance.
violet 1966 beetle
[edit] Interior
Many Beetle owners try to keep their Beetle interior stock. Others will fit a sound system, which usually consists of a head unit and possibly some speakers and a subwoofer (usually mounted in the front of the car). Aftermarket steering wheels can be added along with auxiliary gauges. For a true race look, the interior can be stripped and a full roll cage installed, along with bucket seats and race harnesses although bucket seating is already the default seating for a Beetle.
The VW Type 1 chassis, being easily separated from its original body without removal of engine, transmission, or suspension, has provided the basis for countless custom re-bodyings, usually of fiberglass and usually replicating other, less humble vehicles. Mercedes, MG and Porsche replicas are among the popular choices. The more successful being the Sterling sports car in the 70's Fiberglass body kits with its all original body styling. These "kit cars", although derided by many for their lack of authenticity, provide to their owners a much cheaper, often more-reliable means of enjoying a dream vehicle.
[edit] Power
Volvo B18/B20 engine fitted to VW Beetle for racing.
Because most parts of the flat-4 engine other than the crankcase are bolted on, they are easily exchanged with larger or more high-performance items. The standard VW engine has been modified from 1600 cc (the largest factory-produced Type 1 engine) to configurations well over 2400 cc using larger piston/cylinder kits, turbochargers, and other performance-enhancing parts. A variety of other powerplants, including the VW Type 4 (also used in the 914) 2-liter flat four, Chevy Corvair and Porsche 911 flat sixes have been used. Even the turbocharged flat 4s from Subaru or Alfa Romeo have been used as well. Kits for installing Rover V8 engines have also been available. These variants tend to be mated to the stronger Type 2 (Bus, Combi) transmission. Dual carb setups are very common on Beetles (especially the 1600 cc dual port engine) as well as EFI. Also a wide range of exhaust systems are available. 4-into-1 headers are very popular, and are often used with a stinger, glasspack, or more modern "quiet pack" mufflers. The world record for fastest and quickest four cylinder 1/4 mile drag vehicle is held by a type 1 based engine built and maintained by vwparadise of San Marcos California. Its official run is 6.60 @ 203.94 mph quarter-mile although unofficially the quickest & fastest has been a 6.53 at 209.98 mph.[20]
Beetle
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"Beetles" redirects here. For the band, see The Beatles.
This article is about the insect. For other uses, see Beetle (disambiguation).
Beetle
Fossil range: 299–0 Ma
PreЄ
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Early Permian - Recent
Phyllobius calcaratus, a species of weevil
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Subclass: Pterygota
Infraclass: Neoptera
Superorder: Endopterygota
Order: Coleoptera
Linnaeus, 1758
Suborders
Adephaga
Archostemata
Myxophaga
Polyphaga
See subgroups of the order Coleoptera
Beetles are the group of insects with the largest number of known species. They are classified in the order Coleoptera (pronounced /ˌkoʊliˈɒptərə/; from Greek κολεός, koleos, "sheath"; and πτερόν, pteron, "wing", thus "sheathed wing"), which contains more described species than in any other order in the animal kingdom, constituting about 25% of all known life-forms.[1] 40% of all described insect species are beetles (about 350,000 species[1]), and new species are frequently discovered. Estimates put the total number of species, described and undescribed, at between 5 and 8 million.[citation needed] The largest family also belongs to this order—the weevils, or snout beetles, Curculionidae.
Beetles can be found in almost all habitats, but are not known to occur in the sea or in the polar regions. They interact with their ecosystems in several ways. They often feed on plants and fungi, break down animal and plant debris, and eat other invertebrates. Some species are prey of various animals including birds and mammals. Certain species are agricultural pests, such as the Colorado potato beetle Leptinotarsa decemlineata, the boll weevil Anthonomus grandis, the red flour beetle Tribolium castaneum, and the mungbean or cowpea beetle Callosobruchus maculatus, while other species of beetles are important controls of agricultural pests. For example, beetles in the family Coccinellidae ("ladybirds" or "ladybugs") consume aphids, scale insects, thrips, and other plant-sucking insects that damage crops.
Contents
[hide]
* 1 Description
* 2 Development
* 3 Physiology and behaviour
o 3.1 Reproduction
o 3.2 Defense
o 3.3 Feeding
o 3.4 Adaptations to the environment
* 4 Evolutionary history and classification
* 5 Impact on humans
o 5.1 Pests
o 5.2 Beneficial organisms
o 5.3 Beetles in ancient Egypt and other cultures
* 6 Study and collection
* 7 See also
* 8 References
o 8.1 General references
o 8.2 Cited references
* 9 External links
[edit] Description
The name "Coleoptera" was given by Aristotle for the hardened shield-like forewing (coleo = shield + ptera = wing).[1]
A cockchafer with its elytra raised, exposing the membranous flight wings, where the veins are visible
Trogodendron fasciculatum, a clerid beetle with bright yellow antennae
Tiger beetle of genus Lophyra
The extremely colourful Golden Stag Beetle
Other characters of this group which are believed to be monophyletic include a holometabolous life cycle; having a prothorax that is distinct from and freely articulating with the mesothorax; the meso- and meta-thoracic segments fusing to form a pterothorax; a depressed body shape with the legs on the ventral surface; the coxae of legs recessed into cavities formed by heavily sclerotized thoracic sclerites; the abdominal sternites more sclerotized than the tergites; antennae with 11 or fewer segments; and terminal genitalic appendages retracted into the abdomen and invisible at rest.[1]
The general anatomy of beetles is quite uniform, although specific organs and appendages may vary greatly in appearance and function between the many families in the order. Like all insects, beetles' bodies are divided into three sections: the head, the thorax, and the abdomen. When viewed from below, the thorax is that part from which all three pairs of legs and both pairs of wings arise. The abdomen is everything posterior to the thorax. When viewed from above, most beetles appear to have three clear sections, but this is deceptive: on the beetle's upper surface, the middle "section" is a hard plate called the pronotum, which is only the front part of the thorax; the back part of the thorax is concealed by the beetle's wings. Like all arthropods, beetles are segmented organisms, and all three of the major sections of the body are themselves composed of several further segments, although these are not always readily discernible. This further segmentation is usually best seen on the abdomen.
Beetles are generally characterised by a particularly hard exoskeleton and hard forewings (elytra). The beetle's exoskeleton is made up of numerous plates called sclerites, separated by thin sutures. This design creates the armoured defences of the beetle while maintaining flexibility. The elytra are not used for flight, but tend to cover the hind part of the body and protect the second pair of wings (alae). The elytra must be raised in order to move the hind flight wings. A beetle's flight wings are crossed with veins and are folded after landing, often along these veins, and are stored below the elytra.
In some beetles, the ability to fly has been lost. These include the ground beetles (family Carabidae) and some "true weevils" (family Curculionidae), but also some desert and cave-dwelling species of other families. Many of these species have the two elytra fused together, forming a solid shield over the abdomen. In a few families, both the ability to fly and the elytra have been lost, with the best known example being the glow-worms of the family Phengodidae, in which the females are larviform throughout their lives.
Beetles have mouthparts similar to those of grasshoppers. Of these parts, the most commonly known are probably the mandibles, which appear as large pincers on the front of some beetles. The mandibles are a pair of hard, often tooth-like structures that move horizontally to grasp, crush, or cut food or enemies (see defence, below). Two pairs of finger-like appendages are found around the mouth in most beetles, serving to move food into the mouth. These are the maxillary and labial palpi.
The eyes are compound and may display remarkable adaptability, as in the case of whirligig beetles (family Gyrinidae), in which the eyes are split to allow a view both above and below the waterline. Other species also have divided eyes — some longhorn beetles (family Cerambycidae) and weevils — while many beetles have eyes that are notched to some degree. A few beetle genera also possess ocelli, which are small, simple eyes usually situated farther back on the head (on the vertex).
Beetles' antennae are primarily organs of smell, but may also be used to feel out a beetle's environment physically. They may also be used in some families during mating, or among a few beetles for defence. Antennae vary greatly in form within the Coleoptera, but are often similar within any given family. In some cases, males and females of the same species will have different antennal forms. Antennae may be clavate (flabellate and lamellate are sub-forms of clavate, or clubbed antennae), filiform, geniculate, moniliform, pectinate, or serrate. For images of these antennal forms see antenna (biology).
Acilius sulcatus, a diving beetle showing hind legs adapted for life in water
The legs, which are multi-segmented, end in two to five small segments called tarsi. Like many other insect orders beetles bear claws, usually one pair, on the end of the last tarsal segment of each leg. While most beetles use their legs for walking, legs may be variously modified and adapted for other uses. Among aquatic families — Dytiscidae, Haliplidae, many species of Hydrophilidae and others — the legs, most notably the last pair, are modified for swimming and often bear rows of long hairs to aid this purpose. Other beetles have fossorial legs that are widened and often spined for digging. Species with such adaptations are found among the scarabs, ground beetles, and clown beetles (family Histeridae). The hind legs of some beetles, such as flea beetles (within Chrysomelidae) and flea weevils (within Curculionidae), are enlarged and designed for jumping.
Oxygen is obtained via a tracheal system. Air enters a series of tubes along the body through openings called spiracles, and is then taken into increasingly finer fibres. Pumping movements of the body force the air through the system.
Beetles have hemolymph instead of blood, and the open circulatory system of the beetle is driven by a tube-like heart attached to the top inside of the thorax.
[edit] Development
Scarabaeiform larva of the cockchafer, Melolontha melolontha
Beetles are endopterygotes with complete metamorphosis.
A single female may lay from several dozen to several thousand eggs during her lifetime. Eggs are usually laid according to the substrate the larva will feed on upon hatching. Among others, they can be laid loose in the substrate (e.g. flour beetle), laid in clumps on leaves (e.g. Colorado potato beetle), or individually attached (e.g. mungbean beetle and other seed borers) or buried in the medium (e.g. carrot weevil).
The larva is usually the principal feeding stage of the beetle life cycle. Larvae tend to feed voraciously once they emerge from their eggs. Some feed externally on plants, such as those of certain leaf beetles, while others feed within their food sources. Examples of internal feeders are most Buprestidae and longhorn beetles. The larvae of many beetle families are predatory like the adults (ground beetles, ladybirds, rove beetles). The larval period varies between species but can be as long as several years.
Beetles may be preyed upon by other insects such as robberflies
Beetle larvae can be differentiated from other insect larvae by their hardened, often darkened head, the presence of chewing mouthparts, and spiracles along the sides of the body. Like adult beetles, the larvae are varied in appearance, particularly between beetle families. Beetles whose larvae are somewhat flattened and are highly mobile are the ground beetles, some rove beetles, and others; their larvae are described as campodeiform. Some beetle larvae resemble hardened worms with dark head capsules and minute legs. These are elateriform larvae, and are found in the click beetle (Elateridae) and darkling beetle (Tenebrionidae) families. Some elateriform larvae of click beetles are known as wireworms. Beetles in the families of the Scarabaeoidea have short, thick larvae described as scarabaeiform, but more commonly known as grubs.
All beetle larvae go through several instars, which are the developmental stages between each moult. In many species the larvae simply increase in size with each successive instar as more food is consumed. In some cases, however, more dramatic changes occur. Among certain beetle families or genera, particularly those that exhibit parasitic lifestyles, the first instar (the planidium) is highly mobile in order to search out a host, while the following instars are more sedentary and remain on or within their host. This is known as hypermetamorphosis; examples include the blister beetles (family Meloidae) and some rove beetles, particularly those of the genus Aleochara.
As with all endopterygotes, beetle larvae pupate, and from this pupa emerges a fully formed, sexually mature adult beetle, or imago. Adults have an extremely variable lifespan, from weeks to years, depending on the species.
[edit] Physiology and behaviour
[edit] Reproduction
Punctate Flower Chafers mating
A flower beetle, Eudicella gralli, from the forests of Central Africa. The iridescent elytra are used in indigenous marriage ceremonies.
Beetles may display extremely intricate behaviour when mating. Pheromone communication is thought to be important in the location of a mate.
Conflict can play a part in the mating rituals of species such as burying beetles (genus Nicrophorus) where conflicts between males and females rage until only one of each is left, thus ensuring reproduction by the strongest and fittest. Many male beetles are territorial and will fiercely defend their small patch of territory from intruding males. In such species, the males may often have horns on the head and/or thorax, making their overall body lengths greater than those of the females, unlike most insects.
Pairing is generally short but in some cases will last for several hours. During pairing sperm cells are transferred to the female to fertilise the egg.
Parental care varies between species, ranging from the simple laying of eggs under a leaf to certain scarab beetles, which construct underground structures complete with a supply of dung to house and feed their young. Other beetles are leaf rollers, biting sections of leaves to cause them to curl inwards, then laying their eggs, thus protected, inside.
[edit] Defense
Brachinus sp., a bombardier beetle
Beetles and their larvae have a variety of strategies to avoid being attacked by predators or parasitoids. These include camouflage, mimicry, toxicity, and active defense.
Camouflage involves the use of colouration or shape to blend into the surrounding environment. This sort of protective coloration is common and widespread among beetle families, especially those that feed on wood or vegetation, such as many of the leaf beetles (family Chrysomelidae) or weevils. In some of these species, sculpturing or various coloured scales or hairs cause the beetle to resemble bird dung or other inedible objects. Many of those that live in sandy environments blend in with the coloration of the substrate.
Another defence that often uses colour or shape to deceive potential enemies is mimicry. A number of longhorn beetles (family Cerambycidae) bear a striking resemblance to wasps, which helps them avoid predation even though the beetles are in fact harmless. This defence can be found to a lesser extent in other beetle families, such as the scarab beetles. Beetles may combine their colour mimicry with behavioural mimicry, acting like the wasps they already closely resemble. Many beetle species, including ladybirds, blister beetles, and lycid beetles can secrete distasteful or toxic substances to make them unpalatable or even poisonous. These same species often exhibit aposematism, where bright or contrasting colour patterns warn away potential predators, and there are, not surprisingly, a great many beetles and other insects that mimic these chemically-protected species.
Large ground beetles and longhorn beetles may defend themselves using strong mandibles and/or spines or horns to forcibly persuade a predator to seek out easier prey. Others, such as bombardier beetles (within Carabidae), may spray chemicals from their abdomen to repel predators.
[edit] Feeding
A Fiddler Beetle feeding from a flowering Cotoneaster glaucophyllus shrub
Besides being abundant and varied, the Coleoptera are able to exploit the wide diversity of food sources available in their many habitats. Some are omnivores, eating both plants and animals. Other beetles are highly specialised in their diet. Many species of leaf beetles, longhorn beetles, and weevils are very host specific, feeding on only a single species of plant. Ground beetles and rove beetles (family Staphylinidae), among others, are primarily carnivorous and will catch and consume many other arthropods and small prey such as earthworms and snails. While most predatory beetles are generalists, a few species have more specific prey requirements or preferences.
Decaying organic matter is a primary diet for many species. This can range from dung, which is consumed by coprophagous species such as certain scarab beetles (family Scarabaeidae), to dead animals, which are eaten by necrophagous species such as the carrion beetles (family Silphidae). Some of the beetles found within dung and carrion are in fact predatory, such as the clown beetles, preying on the larvae of coprophagous and necrophagous insects.
[edit] Adaptations to the environment
Aquatic beetles use several techniques for retaining air beneath the water's surface. Beetles of the family Dytiscidae hold air between the abdomen and the elytra when diving. Hydrophilidae have hairs on their under surface that retain a layer of air against their bodies. Adult crawling water beetles use both their elytra and their hind coxae (the basal segment of the back legs) in air retention[2] while whirligig beetles simply carry an air bubble down with them whenever they dive.
[edit] Evolutionary history and classification
Sphaerius acaroides, a member of the small suborder Myxophaga
While some authorities[vague] believe modern beetles began about 140 million years ago, research announced in 2007 showed that beetles may have entered the fossil record during the Lower Permian, about 265 to 300 million years ago.[3]
The four extant suborders of beetle are these:
* Polyphaga is the largest suborder, containing more than 300,000 described species in more than 170 families, including rove beetles (Staphylinidae), scarab beetles (Scarabaeidae), blister beetles (Meloidae), stag beetles (Lucanidae) and true weevils (Curculionidae). These beetles can be identified by the cervical sclerites (hardened parts of the head used as points of attachment for muscles) absent in the other suborders.
* Adephaga contains about 10 families of largely predatory beetles, includes ground beetles (Carabidae), Dytiscidae and whirligig beetles (Gyrinidae). In these beetles the testes are tubular and the first abdominal sternum (a plate of the exoskeleton) is divided by the hind coxae (the basal joints of the beetle's legs).
* Archostemata contains four families of mainly wood-eating beetles, including reticulated beetles (Cupedidae) and the telephone-pole beetle.
* Myxophaga contains about 100 described species in four families, mostly very small, including Hydroscaphidae and the genus Sphaerius.
These suborders diverged in the Permian and Triassic. Their phylogenetic relationship is uncertain, with the most popular hypothesis being that Polyphaga and Myxophaga are most closely related, with Adephaga as the sister group to those two, and Archostemata as sister to the other three collectively.
There are about 350,000 species of beetles. Such a large number of species poses special problems for classification, with some families consisting of thousands of species and needing further division into subfamilies and tribes.
[edit] Impact on humans
[edit] Pests
Colorado potato beetle (Leptinotarsa decemlineata) larvae
Many agricultural, forestry, and household insect pests are beetles. These include the following:
* The Colorado potato beetle, Leptinotarsa decemlineata, is a notorious pest of potato plants. Crops are destroyed and the beetle can only be treated by employing expensive pesticides, many of which it has begun to develop resistance to. As well as potatoes, suitable hosts can be a number of plants from the potato family (Solanaceae), such as nightshade, tomato, aubergine and capsicum.
* The boll weevil, Anthonomus grandis, has cost cotton producers in the United States billions of dollars since it first entered that country.
* The bark beetles Hylurgopinus rufipes and Scolytus multistriatus, the elm leaf beetle, Pyrrhalta luteola, and other beetles attack elm trees. The bark beetles are important elm pests because they carry Dutch elm disease as they move from infected breeding sites to feed on healthy elm trees. The spread of the fungus by the beetle has led to the devastation of elm trees in many parts of the Northern Hemisphere, notably in Europe and North America.
Red flour beetle, Tribolium castaneum
* Flour beetles are pests of cereal silos. They feed on wheat and other grains and are adapted to survive in very dry environments. They are a major pest in the agricultural industry and are highly resistant to insecticides.
* The death watch beetle, Xestobium rufovillosum, (family Anobiidae) is of considerable importance as a pest of older wooden buildings in Great Britain. It attacks hardwoods such as oak and chestnut, always where some fungal decay has taken or is taking place. It is thought that the actual introduction of the pest into buildings takes place at the time of construction.
* Asian long-horned beetle
* Citrus long-horned beetle
* Rose chafer, Macrodactylus subspinosus
* Western corn rootworm
* Coconut hispine beetle, Brontispa longissima, feeds on young leaves and damages seedlings and mature coconut palms. On September 27, 2007, Philippines' Metro Manila and 26 provinces were quarantined due to having been infested with this pest (to save the $800-million Philippine coconut industry).[4]
* The mountain pine beetle normally attacks mature or weakened lodgepole pine. Under the right circumstances outbreaks make it the most destructive insect pest of mature pine forests. The current infestation in British Columbia is the largest Canada has ever seen.[5]
[edit] Beneficial organisms
Coccinella septempunctata, a beneficial beetle
* Both the larvae and adults of some ladybirds (family Coccinellidae) are found in aphid colonies. Other lady beetles feed on scale insects and mealybugs. If normal food sources are scarce, they may feed on other things, such as small caterpillars, young plant bugs, honeydew and nectar.
* Ground beetles (family Carabidae) are common predators of many different insects and other arthropods, including fly eggs, caterpillars, wireworms and others.
* Plant-feeding beetles are often important beneficial insects, controlling problem weeds. Some flea beetles of the genus Aphthona feed on leafy spurge, a considerable weed of rangeland in western North America.
* Dung beetles (Coleoptera, Scarabidae) have been successfully used to reduce the populations of pestilent flies and parasitic worms that breed in cattle dung. The beetles make the dung unavailable to breeding pests by quickly rolling and burying it in the soil, with the added effect of improving soil fertility and nutrient cycling. The Australian Dung Beetle Project (1965-1985), led by Dr. George Bornemissza of the Commonwealth Scientific and Industrial Research Organisation introduced species of dung beetle to Australia from South Africa and Europe and effectively reduced the bush fly population by 90%.
Some farmers develop beetle banks to foster and provide cover for beneficial beetles.
Beetles of the Dermestidae family are often used in taxidermy to clean bones of remaining flesh.
[edit] Beetles in ancient Egypt and other cultures
Ancient Egyptian scene depicting a scarab beetle
Beetle collection at the Melbourne Museum, Australia
Several species of dung beetle, most notably Scarabaeus sacer (often referred to as "scarab"), enjoyed a sacred status among the ancient Egyptians, as the creatures were likened to the major god Khepri. Some scholars suggest that the Egyptians' practice of making mummies was inspired by the brooding process of the beetle.[citation needed] Many thousands of amulets and stamp seals have been excavated that depict the scarab. In many artifacts, the scarab is depicted pushing the sun along its course in the sky, much as scarabs push or roll balls of dung to their brood sites. During and following the New Kingdom, scarab amulets were often placed over the heart of the mummified deceased.
Some tribal groups, particularly in tropical parts of the world, use the colourful, iridescent elytra of certain beetles, especially certain Scarabaeidae, in ceremonies and as adornment.
[edit] Study and collection
The study of beetles is called coleopterology (from Coleoptera, see above, and Greek -λογία, -logia), and its practitioners are coleopterists (see this list). Coleopterists have formed organisations to facilitate the study of beetles. Among these is The Coleopterists Society, an international organisation based in the United States. Such organisations may have both professionals and amateurs interested in beetles as members.
Research in this field is often published in peer-reviewed journals specific to the field of coleopterology, though journals dealing with general entomology also publish many papers on various aspects of beetle biology. Some of the journals specific to beetle
From Wikipedia, the free encyclopedia
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This article is about the insect. For other uses, see Beetle (disambiguation).
Beetle
Fossil range: 299–0 Ma
PreЄ
Є
O
S
D
C
P
T
J
K
Pg
N
Early Permian - Recent
Phyllobius calcaratus, a species of weevil
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Subclass: Pterygota
Infraclass: Neoptera
Superorder: Endopterygota
Order: Coleoptera
Linnaeus, 1758
Suborders
Adephaga
Archostemata
Myxophaga
Polyphaga
See subgroups of the order Coleoptera
Beetles are the group of insects with the largest number of known species. They are classified in the order Coleoptera (pronounced /ˌkoʊliˈɒptərə/; from Greek κολεός, koleos, "sheath"; and πτερόν, pteron, "wing", thus "sheathed wing"), which contains more described species than in any other order in the animal kingdom, constituting about 25% of all known life-forms.[1] 40% of all described insect species are beetles (about 350,000 species[1]), and new species are frequently discovered. Estimates put the total number of species, described and undescribed, at between 5 and 8 million.[citation needed] The largest family also belongs to this order—the weevils, or snout beetles, Curculionidae.
Beetles can be found in almost all habitats, but are not known to occur in the sea or in the polar regions. They interact with their ecosystems in several ways. They often feed on plants and fungi, break down animal and plant debris, and eat other invertebrates. Some species are prey of various animals including birds and mammals. Certain species are agricultural pests, such as the Colorado potato beetle Leptinotarsa decemlineata, the boll weevil Anthonomus grandis, the red flour beetle Tribolium castaneum, and the mungbean or cowpea beetle Callosobruchus maculatus, while other species of beetles are important controls of agricultural pests. For example, beetles in the family Coccinellidae ("ladybirds" or "ladybugs") consume aphids, scale insects, thrips, and other plant-sucking insects that damage crops.
Contents
[hide]
* 1 Description
* 2 Development
* 3 Physiology and behaviour
o 3.1 Reproduction
o 3.2 Defense
o 3.3 Feeding
o 3.4 Adaptations to the environment
* 4 Evolutionary history and classification
* 5 Impact on humans
o 5.1 Pests
o 5.2 Beneficial organisms
o 5.3 Beetles in ancient Egypt and other cultures
* 6 Study and collection
* 7 See also
* 8 References
o 8.1 General references
o 8.2 Cited references
* 9 External links
[edit] Description
The name "Coleoptera" was given by Aristotle for the hardened shield-like forewing (coleo = shield + ptera = wing).[1]
A cockchafer with its elytra raised, exposing the membranous flight wings, where the veins are visible
Trogodendron fasciculatum, a clerid beetle with bright yellow antennae
Tiger beetle of genus Lophyra
The extremely colourful Golden Stag Beetle
Other characters of this group which are believed to be monophyletic include a holometabolous life cycle; having a prothorax that is distinct from and freely articulating with the mesothorax; the meso- and meta-thoracic segments fusing to form a pterothorax; a depressed body shape with the legs on the ventral surface; the coxae of legs recessed into cavities formed by heavily sclerotized thoracic sclerites; the abdominal sternites more sclerotized than the tergites; antennae with 11 or fewer segments; and terminal genitalic appendages retracted into the abdomen and invisible at rest.[1]
The general anatomy of beetles is quite uniform, although specific organs and appendages may vary greatly in appearance and function between the many families in the order. Like all insects, beetles' bodies are divided into three sections: the head, the thorax, and the abdomen. When viewed from below, the thorax is that part from which all three pairs of legs and both pairs of wings arise. The abdomen is everything posterior to the thorax. When viewed from above, most beetles appear to have three clear sections, but this is deceptive: on the beetle's upper surface, the middle "section" is a hard plate called the pronotum, which is only the front part of the thorax; the back part of the thorax is concealed by the beetle's wings. Like all arthropods, beetles are segmented organisms, and all three of the major sections of the body are themselves composed of several further segments, although these are not always readily discernible. This further segmentation is usually best seen on the abdomen.
Beetles are generally characterised by a particularly hard exoskeleton and hard forewings (elytra). The beetle's exoskeleton is made up of numerous plates called sclerites, separated by thin sutures. This design creates the armoured defences of the beetle while maintaining flexibility. The elytra are not used for flight, but tend to cover the hind part of the body and protect the second pair of wings (alae). The elytra must be raised in order to move the hind flight wings. A beetle's flight wings are crossed with veins and are folded after landing, often along these veins, and are stored below the elytra.
In some beetles, the ability to fly has been lost. These include the ground beetles (family Carabidae) and some "true weevils" (family Curculionidae), but also some desert and cave-dwelling species of other families. Many of these species have the two elytra fused together, forming a solid shield over the abdomen. In a few families, both the ability to fly and the elytra have been lost, with the best known example being the glow-worms of the family Phengodidae, in which the females are larviform throughout their lives.
Beetles have mouthparts similar to those of grasshoppers. Of these parts, the most commonly known are probably the mandibles, which appear as large pincers on the front of some beetles. The mandibles are a pair of hard, often tooth-like structures that move horizontally to grasp, crush, or cut food or enemies (see defence, below). Two pairs of finger-like appendages are found around the mouth in most beetles, serving to move food into the mouth. These are the maxillary and labial palpi.
The eyes are compound and may display remarkable adaptability, as in the case of whirligig beetles (family Gyrinidae), in which the eyes are split to allow a view both above and below the waterline. Other species also have divided eyes — some longhorn beetles (family Cerambycidae) and weevils — while many beetles have eyes that are notched to some degree. A few beetle genera also possess ocelli, which are small, simple eyes usually situated farther back on the head (on the vertex).
Beetles' antennae are primarily organs of smell, but may also be used to feel out a beetle's environment physically. They may also be used in some families during mating, or among a few beetles for defence. Antennae vary greatly in form within the Coleoptera, but are often similar within any given family. In some cases, males and females of the same species will have different antennal forms. Antennae may be clavate (flabellate and lamellate are sub-forms of clavate, or clubbed antennae), filiform, geniculate, moniliform, pectinate, or serrate. For images of these antennal forms see antenna (biology).
Acilius sulcatus, a diving beetle showing hind legs adapted for life in water
The legs, which are multi-segmented, end in two to five small segments called tarsi. Like many other insect orders beetles bear claws, usually one pair, on the end of the last tarsal segment of each leg. While most beetles use their legs for walking, legs may be variously modified and adapted for other uses. Among aquatic families — Dytiscidae, Haliplidae, many species of Hydrophilidae and others — the legs, most notably the last pair, are modified for swimming and often bear rows of long hairs to aid this purpose. Other beetles have fossorial legs that are widened and often spined for digging. Species with such adaptations are found among the scarabs, ground beetles, and clown beetles (family Histeridae). The hind legs of some beetles, such as flea beetles (within Chrysomelidae) and flea weevils (within Curculionidae), are enlarged and designed for jumping.
Oxygen is obtained via a tracheal system. Air enters a series of tubes along the body through openings called spiracles, and is then taken into increasingly finer fibres. Pumping movements of the body force the air through the system.
Beetles have hemolymph instead of blood, and the open circulatory system of the beetle is driven by a tube-like heart attached to the top inside of the thorax.
[edit] Development
Scarabaeiform larva of the cockchafer, Melolontha melolontha
Beetles are endopterygotes with complete metamorphosis.
A single female may lay from several dozen to several thousand eggs during her lifetime. Eggs are usually laid according to the substrate the larva will feed on upon hatching. Among others, they can be laid loose in the substrate (e.g. flour beetle), laid in clumps on leaves (e.g. Colorado potato beetle), or individually attached (e.g. mungbean beetle and other seed borers) or buried in the medium (e.g. carrot weevil).
The larva is usually the principal feeding stage of the beetle life cycle. Larvae tend to feed voraciously once they emerge from their eggs. Some feed externally on plants, such as those of certain leaf beetles, while others feed within their food sources. Examples of internal feeders are most Buprestidae and longhorn beetles. The larvae of many beetle families are predatory like the adults (ground beetles, ladybirds, rove beetles). The larval period varies between species but can be as long as several years.
Beetles may be preyed upon by other insects such as robberflies
Beetle larvae can be differentiated from other insect larvae by their hardened, often darkened head, the presence of chewing mouthparts, and spiracles along the sides of the body. Like adult beetles, the larvae are varied in appearance, particularly between beetle families. Beetles whose larvae are somewhat flattened and are highly mobile are the ground beetles, some rove beetles, and others; their larvae are described as campodeiform. Some beetle larvae resemble hardened worms with dark head capsules and minute legs. These are elateriform larvae, and are found in the click beetle (Elateridae) and darkling beetle (Tenebrionidae) families. Some elateriform larvae of click beetles are known as wireworms. Beetles in the families of the Scarabaeoidea have short, thick larvae described as scarabaeiform, but more commonly known as grubs.
All beetle larvae go through several instars, which are the developmental stages between each moult. In many species the larvae simply increase in size with each successive instar as more food is consumed. In some cases, however, more dramatic changes occur. Among certain beetle families or genera, particularly those that exhibit parasitic lifestyles, the first instar (the planidium) is highly mobile in order to search out a host, while the following instars are more sedentary and remain on or within their host. This is known as hypermetamorphosis; examples include the blister beetles (family Meloidae) and some rove beetles, particularly those of the genus Aleochara.
As with all endopterygotes, beetle larvae pupate, and from this pupa emerges a fully formed, sexually mature adult beetle, or imago. Adults have an extremely variable lifespan, from weeks to years, depending on the species.
[edit] Physiology and behaviour
[edit] Reproduction
Punctate Flower Chafers mating
A flower beetle, Eudicella gralli, from the forests of Central Africa. The iridescent elytra are used in indigenous marriage ceremonies.
Beetles may display extremely intricate behaviour when mating. Pheromone communication is thought to be important in the location of a mate.
Conflict can play a part in the mating rituals of species such as burying beetles (genus Nicrophorus) where conflicts between males and females rage until only one of each is left, thus ensuring reproduction by the strongest and fittest. Many male beetles are territorial and will fiercely defend their small patch of territory from intruding males. In such species, the males may often have horns on the head and/or thorax, making their overall body lengths greater than those of the females, unlike most insects.
Pairing is generally short but in some cases will last for several hours. During pairing sperm cells are transferred to the female to fertilise the egg.
Parental care varies between species, ranging from the simple laying of eggs under a leaf to certain scarab beetles, which construct underground structures complete with a supply of dung to house and feed their young. Other beetles are leaf rollers, biting sections of leaves to cause them to curl inwards, then laying their eggs, thus protected, inside.
[edit] Defense
Brachinus sp., a bombardier beetle
Beetles and their larvae have a variety of strategies to avoid being attacked by predators or parasitoids. These include camouflage, mimicry, toxicity, and active defense.
Camouflage involves the use of colouration or shape to blend into the surrounding environment. This sort of protective coloration is common and widespread among beetle families, especially those that feed on wood or vegetation, such as many of the leaf beetles (family Chrysomelidae) or weevils. In some of these species, sculpturing or various coloured scales or hairs cause the beetle to resemble bird dung or other inedible objects. Many of those that live in sandy environments blend in with the coloration of the substrate.
Another defence that often uses colour or shape to deceive potential enemies is mimicry. A number of longhorn beetles (family Cerambycidae) bear a striking resemblance to wasps, which helps them avoid predation even though the beetles are in fact harmless. This defence can be found to a lesser extent in other beetle families, such as the scarab beetles. Beetles may combine their colour mimicry with behavioural mimicry, acting like the wasps they already closely resemble. Many beetle species, including ladybirds, blister beetles, and lycid beetles can secrete distasteful or toxic substances to make them unpalatable or even poisonous. These same species often exhibit aposematism, where bright or contrasting colour patterns warn away potential predators, and there are, not surprisingly, a great many beetles and other insects that mimic these chemically-protected species.
Large ground beetles and longhorn beetles may defend themselves using strong mandibles and/or spines or horns to forcibly persuade a predator to seek out easier prey. Others, such as bombardier beetles (within Carabidae), may spray chemicals from their abdomen to repel predators.
[edit] Feeding
A Fiddler Beetle feeding from a flowering Cotoneaster glaucophyllus shrub
Besides being abundant and varied, the Coleoptera are able to exploit the wide diversity of food sources available in their many habitats. Some are omnivores, eating both plants and animals. Other beetles are highly specialised in their diet. Many species of leaf beetles, longhorn beetles, and weevils are very host specific, feeding on only a single species of plant. Ground beetles and rove beetles (family Staphylinidae), among others, are primarily carnivorous and will catch and consume many other arthropods and small prey such as earthworms and snails. While most predatory beetles are generalists, a few species have more specific prey requirements or preferences.
Decaying organic matter is a primary diet for many species. This can range from dung, which is consumed by coprophagous species such as certain scarab beetles (family Scarabaeidae), to dead animals, which are eaten by necrophagous species such as the carrion beetles (family Silphidae). Some of the beetles found within dung and carrion are in fact predatory, such as the clown beetles, preying on the larvae of coprophagous and necrophagous insects.
[edit] Adaptations to the environment
Aquatic beetles use several techniques for retaining air beneath the water's surface. Beetles of the family Dytiscidae hold air between the abdomen and the elytra when diving. Hydrophilidae have hairs on their under surface that retain a layer of air against their bodies. Adult crawling water beetles use both their elytra and their hind coxae (the basal segment of the back legs) in air retention[2] while whirligig beetles simply carry an air bubble down with them whenever they dive.
[edit] Evolutionary history and classification
Sphaerius acaroides, a member of the small suborder Myxophaga
While some authorities[vague] believe modern beetles began about 140 million years ago, research announced in 2007 showed that beetles may have entered the fossil record during the Lower Permian, about 265 to 300 million years ago.[3]
The four extant suborders of beetle are these:
* Polyphaga is the largest suborder, containing more than 300,000 described species in more than 170 families, including rove beetles (Staphylinidae), scarab beetles (Scarabaeidae), blister beetles (Meloidae), stag beetles (Lucanidae) and true weevils (Curculionidae). These beetles can be identified by the cervical sclerites (hardened parts of the head used as points of attachment for muscles) absent in the other suborders.
* Adephaga contains about 10 families of largely predatory beetles, includes ground beetles (Carabidae), Dytiscidae and whirligig beetles (Gyrinidae). In these beetles the testes are tubular and the first abdominal sternum (a plate of the exoskeleton) is divided by the hind coxae (the basal joints of the beetle's legs).
* Archostemata contains four families of mainly wood-eating beetles, including reticulated beetles (Cupedidae) and the telephone-pole beetle.
* Myxophaga contains about 100 described species in four families, mostly very small, including Hydroscaphidae and the genus Sphaerius.
These suborders diverged in the Permian and Triassic. Their phylogenetic relationship is uncertain, with the most popular hypothesis being that Polyphaga and Myxophaga are most closely related, with Adephaga as the sister group to those two, and Archostemata as sister to the other three collectively.
There are about 350,000 species of beetles. Such a large number of species poses special problems for classification, with some families consisting of thousands of species and needing further division into subfamilies and tribes.
[edit] Impact on humans
[edit] Pests
Colorado potato beetle (Leptinotarsa decemlineata) larvae
Many agricultural, forestry, and household insect pests are beetles. These include the following:
* The Colorado potato beetle, Leptinotarsa decemlineata, is a notorious pest of potato plants. Crops are destroyed and the beetle can only be treated by employing expensive pesticides, many of which it has begun to develop resistance to. As well as potatoes, suitable hosts can be a number of plants from the potato family (Solanaceae), such as nightshade, tomato, aubergine and capsicum.
* The boll weevil, Anthonomus grandis, has cost cotton producers in the United States billions of dollars since it first entered that country.
* The bark beetles Hylurgopinus rufipes and Scolytus multistriatus, the elm leaf beetle, Pyrrhalta luteola, and other beetles attack elm trees. The bark beetles are important elm pests because they carry Dutch elm disease as they move from infected breeding sites to feed on healthy elm trees. The spread of the fungus by the beetle has led to the devastation of elm trees in many parts of the Northern Hemisphere, notably in Europe and North America.
Red flour beetle, Tribolium castaneum
* Flour beetles are pests of cereal silos. They feed on wheat and other grains and are adapted to survive in very dry environments. They are a major pest in the agricultural industry and are highly resistant to insecticides.
* The death watch beetle, Xestobium rufovillosum, (family Anobiidae) is of considerable importance as a pest of older wooden buildings in Great Britain. It attacks hardwoods such as oak and chestnut, always where some fungal decay has taken or is taking place. It is thought that the actual introduction of the pest into buildings takes place at the time of construction.
* Asian long-horned beetle
* Citrus long-horned beetle
* Rose chafer, Macrodactylus subspinosus
* Western corn rootworm
* Coconut hispine beetle, Brontispa longissima, feeds on young leaves and damages seedlings and mature coconut palms. On September 27, 2007, Philippines' Metro Manila and 26 provinces were quarantined due to having been infested with this pest (to save the $800-million Philippine coconut industry).[4]
* The mountain pine beetle normally attacks mature or weakened lodgepole pine. Under the right circumstances outbreaks make it the most destructive insect pest of mature pine forests. The current infestation in British Columbia is the largest Canada has ever seen.[5]
[edit] Beneficial organisms
Coccinella septempunctata, a beneficial beetle
* Both the larvae and adults of some ladybirds (family Coccinellidae) are found in aphid colonies. Other lady beetles feed on scale insects and mealybugs. If normal food sources are scarce, they may feed on other things, such as small caterpillars, young plant bugs, honeydew and nectar.
* Ground beetles (family Carabidae) are common predators of many different insects and other arthropods, including fly eggs, caterpillars, wireworms and others.
* Plant-feeding beetles are often important beneficial insects, controlling problem weeds. Some flea beetles of the genus Aphthona feed on leafy spurge, a considerable weed of rangeland in western North America.
* Dung beetles (Coleoptera, Scarabidae) have been successfully used to reduce the populations of pestilent flies and parasitic worms that breed in cattle dung. The beetles make the dung unavailable to breeding pests by quickly rolling and burying it in the soil, with the added effect of improving soil fertility and nutrient cycling. The Australian Dung Beetle Project (1965-1985), led by Dr. George Bornemissza of the Commonwealth Scientific and Industrial Research Organisation introduced species of dung beetle to Australia from South Africa and Europe and effectively reduced the bush fly population by 90%.
Some farmers develop beetle banks to foster and provide cover for beneficial beetles.
Beetles of the Dermestidae family are often used in taxidermy to clean bones of remaining flesh.
[edit] Beetles in ancient Egypt and other cultures
Ancient Egyptian scene depicting a scarab beetle
Beetle collection at the Melbourne Museum, Australia
Several species of dung beetle, most notably Scarabaeus sacer (often referred to as "scarab"), enjoyed a sacred status among the ancient Egyptians, as the creatures were likened to the major god Khepri. Some scholars suggest that the Egyptians' practice of making mummies was inspired by the brooding process of the beetle.[citation needed] Many thousands of amulets and stamp seals have been excavated that depict the scarab. In many artifacts, the scarab is depicted pushing the sun along its course in the sky, much as scarabs push or roll balls of dung to their brood sites. During and following the New Kingdom, scarab amulets were often placed over the heart of the mummified deceased.
Some tribal groups, particularly in tropical parts of the world, use the colourful, iridescent elytra of certain beetles, especially certain Scarabaeidae, in ceremonies and as adornment.
[edit] Study and collection
The study of beetles is called coleopterology (from Coleoptera, see above, and Greek -λογία, -logia), and its practitioners are coleopterists (see this list). Coleopterists have formed organisations to facilitate the study of beetles. Among these is The Coleopterists Society, an international organisation based in the United States. Such organisations may have both professionals and amateurs interested in beetles as members.
Research in this field is often published in peer-reviewed journals specific to the field of coleopterology, though journals dealing with general entomology also publish many papers on various aspects of beetle biology. Some of the journals specific to beetle
Jumat, 11 September 2009
Description
The name "Coleoptera" was given by Aristotle for the hardened shield-like forewing (coleo = shield + ptera = wing).[1]
Other characters of this group which are believed to be monophyletic include a holometabolous life cycle; having a prothorax that is distinct from and freely articulating with the mesothorax; the meso- and meta-thoracic segments fusing to form a pterothorax; a depressed body shape with the legs on the ventral surface; the coxae of legs recessed into cavities formed by heavily sclerotized thoracic sclerites; the abdominal sternites more sclerotized than the tergites; antennae with 11 or fewer segments; and terminal genitalic appendages retracted into the abdomen and invisible at rest.[1]
The general anatomy of beetles is quite uniform, although specific organs and appendages may vary greatly in appearance and function between the many families in the order. Like all insects, beetles' bodies are divided into three sections: the head, the thorax, and the abdomen. When viewed from below, the thorax is that part from which all three pairs of legs and both pairs of wings arise. The abdomen is everything posterior to the thorax. When viewed from above, most beetles appear to have three clear sections, but this is deceptive: on the beetle's upper surface, the middle "section" is a hard plate called the pronotum, which is only the front part of the thorax; the back part of the thorax is concealed by the beetle's wings. Like all arthropods, beetles are segmented organisms, and all three of the major sections of the body are themselves composed of several further segments, although these are not always readily discernible. This further segmentation is usually best seen on the abdomen.
Beetles are generally characterised by a particularly hard exoskeleton and hard forewings (elytra). The beetle's exoskeleton is made up of numerous plates called sclerites, separated by thin sutures. This design creates the armoured defences of the beetle while maintaining flexibility. The elytra are not used for flight, but tend to cover the hind part of the body and protect the second pair of wings (alae). The elytra must be raised in order to move the hind flight wings. A beetle's flight wings are crossed with veins and are folded after landing, often along these veins, and are stored below the elytra.
In some beetles, the ability to fly has been lost. These include the ground beetles (family Carabidae) and some "true weevils" (family Curculionidae), but also some desert and cave-dwelling species of other families. Many of these species have the two elytra fused together, forming a solid shield over the abdomen. In a few families, both the ability to fly and the elytra have been lost, with the best known example being the glow-worms of the family Phengodidae, in which the females are larviform throughout their lives.
Beetles have mouthparts similar to those of grasshoppers. Of these parts, the most commonly known are probably the mandibles, which appear as large pincers on the front of some beetles. The mandibles are a pair of hard, often tooth-like structures that move horizontally to grasp, crush, or cut food or enemies (see defence, below). Two pairs of finger-like appendages are found around the mouth in most beetles, serving to move food into the mouth. These are the maxillary and labial palpi.
The eyes are compound and may display remarkable adaptability, as in the case of whirligig beetles (family Gyrinidae), in which the eyes are split to allow a view both above and below the waterline. Other species also have divided eyes — some longhorn beetles (family Cerambycidae) and weevils — while many beetles have eyes that are notched to some degree. A few beetle genera also possess ocelli, which are small, simple eyes usually situated farther back on the head (on the vertex).
Beetles' antennae are primarily organs of smell, but may also be used to feel out a beetle's environment physically. They may also be used in some families during mating, or among a few beetles for defence. Antennae vary greatly in form within the Coleoptera, but are often similar within any given family. In some cases, males and females of the same species will have different antennal forms. Antennae may be clavate (flabellate and lamellate are sub-forms of clavate, or clubbed antennae), filiform, geniculate, moniliform, pectinate, or serrate. For images of these antennal forms see antenna (biology).
The legs, which are multi-segmented, end in two to five small segments called tarsi. Like many other insect orders beetles bear claws, usually one pair, on the end of the last tarsal segment of each leg. While most beetles use their legs for walking, legs may be variously modified and adapted for other uses. Among aquatic families — Dytiscidae, Haliplidae, many species of Hydrophilidae and others — the legs, most notably the last pair, are modified for swimming and often bear rows of long hairs to aid this purpose. Other beetles have fossorial legs that are widened and often spined for digging. Species with such adaptations are found among the scarabs, ground beetles, and clown beetles (family Histeridae). The hind legs of some beetles, such as flea beetles (within Chrysomelidae) and flea weevils (within Curculionidae), are enlarged and designed for jumping.
Oxygen is obtained via a tracheal system. Air enters a series of tubes along the body through openings called spiracles, and is then taken into increasingly finer fibres. Pumping movements of the body force the air through the system.
Beetles have hemolymph instead of blood, and the open circulatory system of the beetle is driven by a tube-like heart attached to the top inside of the thorax.
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