Beetles and Weevils: Coleoptera

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BEETLES AND WEEVILS: Coleoptera

GIRAFFE-NECKED WEEVIL (Trachelophorus giraffa): SPECIES ACCOUNTS
GREAT WATER BEETLE (Dytiscus marginalis): SPECIES ACCOUNTS
EUROPEAN STAG BEETLE (Lucanus cervus): SPECIES ACCOUNTS
HERCULES BEETLE (Dynastes hercules): SPECIES ACCOUNTS
SACRED SCARAB (Scarabaeus sacer): SPECIES ACCOUNTS
AMERICAN BURYING BEETLE (Nicrophorus americanus): SPECIES ACCOUNTS
DEVIL'S COACH-HORSE (Ocypus olens): SPECIES ACCOUNTS

PHYSICAL CHARACTERISTICS

Beetles are the largest order in the animal kingdom, with approximately 350,000 species known worldwide. Beetles come in a wide variety of body shapes and sizes. They range in length from 0.02 to 6.7 inches (0.55 to 170 millimeters) and are long or round, cylinder-shaped or flat, slender or heavy-bodied. Their bodies are usually very hard and rigid, but some groups, such as fireflies, soldier beetles, and net-winged beetles, typically have bodies that are soft and flexible. Although many species of beetles are plain black or brown, others have amazing metallic or shimmering colors and patterns. These colors are created by chemicals inside their exoskeletons, or hard outer coverings, or by the physical structure of the surface of the exoskeleton itself. Additional structures on the surface of the exoskeleton also influence color, such as surface texture, waxy coatings, scales, and other hairlike coverings. The colors and coatings of beetles help them to recognize one another and to protect themselves from extreme temperatures, water loss, and predators (PREH-duh-ters) that hunt them for food.

The head has chewing mouthparts that are directed forward or downward. Their jaws are used for cutting or grinding plant and animal tissues or for straining small particles from liquids. However, wrinkled beetles are unable to use their jaws for chewing. Instead, they use their other finger-like mouthparts to handle their food. The mouthparts of some net-winged beetles and weevils are place on the tip of a snout, which makes it easier for them to feed on flowers and seeds.

Beetle antennae (an-TEH-nee), or sense organs, are equipped with very sensitive receptors that help them find food, water, mates, and egg-laying sites. Antennae also help them to determine temperature or detect approaching enemies by sensing changes in air currents. Some ground beetles and rove beetles have special structures on their front legs that are used regularly to clean the antennae to maintain their sensitivity. The antennae are usually shorter than the body but are often much longer in some longhorns and brentid weevils. Males may have elaborate antennal structures that increase the surface area for special chemical receptors that are sensitive to pheromones (FEH-re-moans) released by females of the same species. Pheromones are very special airborne chemicals that help potential mates find one another, sometimes over large distances. The antennae are threadlike, beadlike, elbowed or bent, sawtoothed, comblike, feathery, swollen at the tips or clubshaped, or have some segments flat or platelike.

The compound eyes, or eyes with multiple lenses, are usually well developed and may be partially or completely divided into two parts. For example, the eyes of whirligigs are completely divided. They live on the surface of water. The upper portions of the eyes are used for seeing in the air, while the portions in the water are specialized for seeing under water. Simple eyes, or eyes with only a single lens, are rarely found in beetles but are present in most hide beetles and some rove beetles, as well as a few other groups.

Some beetles, usually males, have horns on their heads, jaws, or the first section of their thorax, or midsection. In the male Hercules beetle, the head and thoracic horns work together to form a powerful pinching device. Other beetles have horns on their legs or wing covers. The size of horns varies within the same species and is influenced by adult body size and conditions that influence larval development. These include diet, temperatures, and moisture. Heredity (hih-REH-dih-ti), the physical traits passed from parent to offspring through genes, also plays an important role in horn development.

Most beetles have two pairs of wings. The hard or leathery forewings are called elytra (el-EE-tra). The elytra cover the last two segments of the thorax, the second pair of wings, and some or all of the abdomen. The elytra not only protect beetles from predators and parasites (PAE-rih-saits), or animals that live on another organism from which they obtain food; the elytra also keep beetles from getting scuffed up as they burrow through the soil and rotten wood. The air space between the elytra and the abdomen in desert species helps to insulate their body from sudden changes in temperature. This same space also gives some aquatic beetles a place to store air so they can breathe under water. The second pair of wings are also called flight wings. They do most of the work in flying beetles, while the elytra are used to help them keep their balance. Desert-dwelling darkling beetles and weevils are often unable to fly because their elytra are permanently joined together and they lack fully developed flight wings. However, this arrangement helps them to conserve moisture.

The legs of beetles are used for burrowing, swimming, crawling, or running. Males of the harlequin beetle, the long-armed chafer, and several large weevils have very long front legs that are probably used for mating defense. Desert darkling beetles living in the Kalahari Desert have long, thin legs that lift them as high as possible above the hot sands. Aquatic beetles have flat and fringed legs and use them like paddles as they swim through water. Their feet are tipped with one or two claws and are sometimes equipped with sticky or brushy pads that help them walk on plants and other surfaces. Some male diving beetles have front feet that work like suction cups to help them hold on to a female as they mate underwater.

The abdomen is usually hidden underneath the elytra, but in rove, clown, and many sap beetles, the elytra are short, leaving some or most of the abdomen exposed. The tip of the abdomen sometimes has small structures that are for egg-laying and mating. The tip of the abdomen is very flexible in some beetles. For example, whirligig beetles use their abdomen to help steer themselves on the surface of the water. In ground beetles the flexible abdominal tip is used as a defensive weapon to aim harmful chemicals at their attackers.

Beetle larvae (LAR-vee), or the young of an animal that must go through certain changes in form before becoming adults, usually do not look like the adults. They are grublike with short legs or wormlike with legs reduced in size or entirely absent. Some predatory species are flat with long legs. The distinct head has chewing mouthparts that are adapted for crushing, grinding, or tearing food. Predatory species may have sucking mouthparts for drinking liquified tissues of their prey. The antennae are small and sometimes difficult to see. They have zero to six simple eyes on either side of the head. The thorax has three distinct sections. The first section may be covered with a broad, dark plate. The legs have six or fewer segments, if they are present at all. The soft abdomen is usually divided into ten segments, but some species have only eight or nine. It is sometimes covered with wartlike or other fleshy structures that help give them traction while moving through soil or rotten wood. The next to last segment may have a pair of projections that are sometimes pincherlike.

The features of adult beetles are clearly visible in the pupae, or insects at the life stage between larvae and adults. Some pupae have their legs and developing wings tightly pressed against the body and cannot move them. In other species these structures are not firmly attached to the body and are flexible and capable of limited movement. In some species the abdomen is capable of some movement. The seams between the movable abdominal segments may have small pinchers on both sides called "gin-traps." The pupa snaps these pinchers together to protect itself from small predators and parasitic mites.

GEOGRAPHIC RANGE

Beetles are found on every continent except Antarctica. They are also found on most islands. Most species prefer certain kinds of soils, climates, and foods and live only in a particular geographical region. A few beetle species have been distributed well beyond their natural distribution through human activity, either accidentally or on purpose. About twenty-five thousand species are known in the United States and Canada.

HABITAT

Beetles live in nearly every terrestrial and freshwater habitat on the Earth, but they are not found in the ocean, on polar ice caps, or on some of the tallest mountain peaks. They live everywhere, from coastal sand dunes to wind-swept rocky fields at 10,000 feet (3,050 meters) above sea level. Most species are found in humid tropical forests. Others inhabit cold mountain streams, parched deserts, standing and flowing freshwater habitats, or deep, dark caverns. They hide under stones and bark, or burrow through the soil and wood. They live in fungus, roots, trunks, branches, stems, leaves, flowers, and fruit. Some beetles spend most of their lives in rotting plants and on dead animals. Beetles are also found in the nests of birds, reptiles, mammals, and social insects. They also live in spaces between sand grains at the seashore, adjacent dunes, and along watercourses. A few species are parasites on the bodies of beavers and other rodents.

DIET

Equipped with chewing mouthparts, beetles are capable of eating almost any organism, living or dead, including funguses, plants, and animals, especially other insects. They also eat animal waste. Numerous fungus feeders attack mushrooms and their relatives, while others eat molds and yeasts mixed with plant sap. Plant-feeding beetles eat leaves, flowers, pollen, nectar, fruits, and seeds. Many species feed inside plant tissues and bore through all parts of plants. Wood-boring beetles are unable to digest wood and must rely on bacteria, yeasts, and funguses living in their digestive systems to break it down. A few species eat the skin, dried blood, and other skin secretions of rodents. Carrion and burying beetles, hide beetles, and others scavenge dead animal tissue. Skin beetles prefer to eat feathers, fur, horns, and hooves. Dung beetles bury large amounts of animal waste for use as food for their larvae. They use their membrane-like jaws to strain out bits of undigested food, bacteria, yeasts, and molds from the waste as food for themselves. Some dung beetles prefer to eat dead animals, funguses, fruit, dead millipedes, or the slime tracks of snails.

Carnivorous beetle larvae feed mainly on liquids and produce digestive chemicals that turn their prey into "soup." This kind of digestion also occurs in some adult ground and rove beetles.

BEHAVIOR AND REPRODUCTION

Some plant-feeding beetles will nibble only the edges of leaves, while others will eat everything. Japanese beetles skeletonize leaves by eating all the soft tissue and leaving behind a network of leaf veins. Species feeding on plants with poisonous or sticky sap must first bleed the leaf of these harmful fluids. Before feeding they will bite the veins supplying the sap to the leaf to cut off the supply of sap and bleed the tissues they are about to eat.

Many predatory species will eat anything they can catch and usually choose to live in habitats where there is plenty of prey. Ground and tiger beetles capture their prey on the run, killing and tearing them into smaller chunks with large and powerful mouthparts. They attack a broad range of beetles, other insects, and invertebrates (in-VER-teh-brehts), or animals without backbones, although some prey only on snails. Many rove and clown beetles hunt for food among the nooks and crannies of leaf litter or in decaying plants or dead animals.

Other species are quite particular about what they eat and have very specialized behaviors for locating their prey. The larvae of fireflies feed only on snails and track down prey by following their slime trails. Checkered and bark-gnawing beetles eat bark beetles. They probably follow the scent of bark beetle pheromones to find them under bark. Ant-loving scarabs eat ant larvae and the nest by following the smell of ant pheromones back to the nest. Whirligig beetles identify prey by using waves across the surface of the water generated by struggling insects.

Aquatic beetles must regularly capture new supplies of fresh air to remain under water. Water scavengers do this by breaking through the surface headfirst. Using their antennae to break through the water surface, they draw a layer of air over their body and store it on the lower surface of their abdomen. Predatory diving beetles break through the surface with the tip of their abdomens to trap an air bubble under their elytra. When the oxygen supply of the bubble is nearly exhausted, the beetle must return to the surface for more air.

Beetles defend themselves from predators with a variety of structures, behaviors, and chemicals. For example, many large scarabs, stag beetles, and longhorns avoid being eaten by simply being too large or frightening in appearance. Sharp horns and big, powerful jaws protect others. Beetles with flat bodies will retreat into tight spaces to get out of reach of predators. Shiny, metallic colors and bold patterns make some species look less beetle-like so they are overlooked by predators. Many weevils and other beetles are plain in color or have blotchy patches of browns, blacks, and grays that make them almost invisible on a background of tree bark. Some beetles are protected because they look or behave as, or mimic, stinging wasps, bees, or ants. The chemical weapons of beetles are produced by special glands or taken directly from their food. These foul-smelling and bad-tasting chemicals are released as sprays from the tip of the abdomen, or dribbled out of leg joints. Bombardier beetles spray a burning, stinging fluid from their abdomens with surprising accuracy. Ladybugs, blister and soldier beetles store defensive chemicals in their blood and release them through their leg joints when attacked. Beetles that feed on toxic milkweeds sometimes use its chemical defenses as their own by storing the plant's chemicals in their own tissues.

Beetles communicate with each other using physical, visual, or chemical means, usually to find a mate. Many species use sound to locate one another. Bess beetles, longhorns, and bark beetles rub parts of their bodies together to make a squeaking sound. Male death-watch beetles bang their heads against the sides of their wooden tunnels to attract females. South African tok-tokkies drum their abdomens against soil and rocks to attract mates.

The best known form of visual communication among beetles is bioluminescence (BI-oh-LU-mih-NEH-sens), or light produced by living organisms. Fireflies produce flashes of light with special tissues in their abdomens to locate and attract mates. The speed and length of each flash is caused by a controlled chemical reaction. Each species has it own light-flashing pattern. The number and speed of the flashes help males and females of the same species to recognize one another. Males typically fly at night, flashing their lights until they see a female respond with her own signal. Upon locating a female, he continues flashing and flies toward the female's signal.

Most beetles depend on chemical communication, or pheromones, to find distant mates or those hidden nearby among tangles of vegetation. Females usually produce pheromones to attract males. Large numbers of males and females may gather in mating swarms, or leks (lehks), to improve their chances of finding a mate. Some beetles find mates at food sources, such as dead animals, animal waste, sap flows, or flowers. Others gather around open patches of ground, rocky outcrops, or lone sign posts. Horned males stake out sapping wounds on a tree or some other food source and wait for the arrival of a hungry female. They use their horns to defend the site against other insects, especially other males of the same species.

Most beetles must mate to reproduce. A few species are capable of parthenogenesis (PAR-thuh-no-JEH-nuh-sihs), or the process by which larvae develop from unfertilized eggs. Courtship behavior in beetles is uncommon. Male ground, tiger, and rove beetles may grasp the female's thorax with their jaws before mating, while some male blister beetles tug on the female's antennae. In most beetles the males simply climb on the back of the female to mate. They may stay there for some time in order to keep other males from mating with her. Males usually mate with several females if they have the opportunity. Females mate just once or with many males.

The life cycle of beetles includes four very distinct stages: egg, larva, pupa, and adult. In a few species of beetles the eggs are kept in the female's body until they hatch. However, most species lay their eggs singly or in batches. Beetles living on the ground simply drop them on the dirt, scatter them in soil rich in decaying plant materials, or place them in or near piles of decaying animal bodies or waste. The eggs of plant-feeding species are placed at the base of suitable food plants, glued to stems and leaves, or placed in the crevices of bark. Others place their eggs inside leaf tissues.

The larvae look nothing like the adults and rarely live with them. They scavenge dead animals and waste, attack roots, tunnel in plant tissues, or bore through wood. The larvae usually molt, or shed their exoskeletons or hard outer coverings, three or more times over a period of weeks or years before reaching the pupal stage. Beetle pupae are usually tucked away in soil or rotten wood, under stones, or inside plant tissues. In cooler climates, most beetles spend the winter in the pupal stage. In some beetles, such as many fireflies, the adult females lack wings and look just like the larvae. But they do have compound eyes and are capable of mating and reproducing. One or more generations of beetles are produced per year, depending on species and climate. Most adults live for weeks or months, but some desert darkling beetles are known to live ten or more years.

Parental care is uncommon among beetles. Some ground beetles build small pits to lay their eggs in and guard and clean them until they hatch. The females of several species of tortoise beetles will guard their eggs and larvae until they pupate. Bess beetles tunnel in rotten wood and live in dense colonies. They make squeaking sounds to communicate with other adults and larvae. The larvae depend on the adults for food. They only eat wood that has already been chewed or digested by the adults. In Europe some female rove beetles maintain and defend their brood tunnels and provide their larvae with algae (AL-jee) to eat. Bark and ambrosia beetles grow a special fungus that is eaten by adult beetles and larvae.

The males and females of some species, such as earth-boring beetles, dung scarabs, and burying beetles, cooperate with their mates to dig nests for their eggs and supply them with animal waste or dead animals. Other insects, such as flies, ants, mites, and other beetles, also compete for these food sources. Dung beetles reduce competition by burying animal waste in underground nests. These specially built tunnels help to keep the waste moist and fresh.

Burying beetles demonstrate the most advanced parental care known in beetles. Males and females bury small, dead animals in an underground chamber and prepare them as food for their young. They chew off the feathers or hair and shape the body into a pear-shaped mass with a small pit on top. They lick the mass to coat it with special chemicals that prevent it from decomposing. The female lays her eggs on the chamber floor, and they soon hatch. Both adults nibble on the mass and spit up fluids into the pit. Females call the young to the pit to feed with a squeaking noise made by rubbing the edge of their elytra against the abdomen. Both adults remain in the chamber until the larvae pupate.

BEETLES AND PEOPLE

Beetles have long captured the imagination of people. Ancient Egyptians used the sacred scarab on walls and carvings to symbolize the Egyptian sun god Ra. Symbols of sacred scarabs were especially popular on objects associated with funerals and human burials. For thousands of years, beetles have appeared on vase paintings, porcelain statuary, precious stones, glass paintings, sculptures, jewelry, and coins. Their images were also used to illustrate important papers and books. Fireflies have long held a special fascination for the Chinese and Japanese and appear often in their art.

Throughout history, artisans have used the likenesses of beetles or parts of their bodies to create jewelry. Today, the elytra of the jewel beetle are used in necklaces, head ornaments, and earrings. In parts of Mexico and Central America, a living beetle, popularly known as the ma'kech, is decorated with brightly colored glass beads, attached to a short chain, and pinned to clothing as a reminder of an ancient legend.

A small number of beetles have become important pests of stored foods, pastures, crops, and timber. Beetles compete with humans for food by feeding on beans, peas, tomatoes, potatoes, melons, gourds, and grains. In temperate forests throughout the world, beetles generally attack trees valued as lumber.

Predatory ground beetles and ladybugs are used to control insect pests around the world. Several kinds of plant-feeding beetles are used to combat harmful weeds. In the 1970s the Australians began a program to import exotic dung scarabs and predatory clown beetles to control biting flies and elminate their breeding sites.

CONSERVATION STATUS

Seventy-two species of beetles are listed by the World Conservation Union (IUCN). Of these, seventeen are listed as Extinct, ten as Critically Endangered, fifteen as Endangered, twenty-seven as Vulnerable, and three as Near Threatened. Extinct means no longer living. Critically Endangered means a species is facing an extremely high risk of extinction in the wild. Endangered means the species is facing a very high risk of extinction in the wild. Vulnerable means facing a high risk of extinction in the wild, and Near Threatened means likely to qualify for a threatened category in the near future. Individual countries also list these and other species as threatened, endangered, or extinct. For example, the United States Fish and Wildlife Service lists four species as Threatened, or likely to become endangered in the foreseeable future, and twelve as Endangered, or in danger of extinction throughout all or a significant portion of range.

TAKE A BEETLE TO LUNCH

Some beetles are an important source of protein and fat. In the South Pacific grubs of the palm weevils are roasted and eaten with great delight. The Chinese fry large water beetles in oil or soak them in salty water. The Aborigines of Australia eat nut-flavored wood-boring grubs after roasting them like marshmallows over a fire. In the United States the larvae of the common mealworm is put inside of lollipops as a curiosity.

State and provincial governments throughout the world have also enacted laws that prohibit the collection, trading, and export of their listed species. All beetles, especially those living in small, specialized habitats, are threatened by habitat loss due to fire, development, electric lights, overgrazing, agricultural expansion, damming of rivers and streams, logging, persistent adverse weather, off-road recreational vehicles, and the introduction of exotic species.

GIRAFFE-NECKED WEEVIL (Trachelophorus giraffa): SPECIES ACCOUNTS

Physical characteristics: This species is black with red elytra. Only the male has a long "neck" and measures up to 0.98 inches (25 millimeters) in length.


Geographic range: Giraffe-necked weevils live in Madagascar.


Habitat: They live in forests.


Diet: The adults feed on the leaves of a small tree, called the giraffe beetle tree.


Behavior and reproduction: Adults rest on leaves in open areas and along roadsides. Females lay their eggs on leaves. The leaves are then rolled up into a protective tube that serves as a food source for the larvae.

Giraffe-necked weevils and people: This species does not impact people or their activities.


Conservation status: This species is not listed as endangered or threatened. ∎

GREAT WATER BEETLE (Dytiscus marginalis): SPECIES ACCOUNTS

Physical characteristics: Adults measure up to 1.4 inches (35 millimeters) in length. The midsection and elytra have pale borders. The elytra of the male are smooth, while those of the female are grooved.


Geographic range: This species is found in Europe.


Biome: Lake and pond


Habitat: Great water beetles live in standing bodies of water with muddy bottoms.


Diet: They eat other aquatic insects, clams, snails, crustaceans, and even tadpoles and small fish.


Behavior and reproduction: Great water beetles breathe underwater by breaking the water surface with the tip of the abdomen and trapping an air bubble under the elytra. Females lay their eggs singly on the stems of aquatic plants. The larvae molt three times in thirty-five to forty days. Mature larvae pupate in damp soil next to water. There is one generation produced each year.


Great water beetles and people: This species is one of the largest and most studied of all water beetles in Europe.


Conservation status: This species is not listed as endangered or threatened. ∎

EUROPEAN STAG BEETLE (Lucanus cervus): SPECIES ACCOUNTS

Physical characteristics: The body of a European stag beetle is dark brown or black. Males have a broad head with antler-like jaws and reach a total length of 1.4 to 2.95 inches (35 to 75 millimeters). Females have smaller heads and jaws and measure 1.2 to 1.8 inches (30 to 45 millimeters).


Geographic range: This species is found in central, southern, and western Europe; Asia Minor; and Syria.


Habitat: The European stag beetle lives in old oak forests.


Diet: The adults feed on sap, while larvae eat rotting wood.


Behavior and reproduction: Males use their big jaws against other males in battles over females. Females lay their eggs in old rotten logs and stumps. The larvae reach adulthood in three to five years. Adults mature in fall but remain in their pupal cases until the following summer.


European stag beetles and people: This species was once thought of as a symbol of evil and bad luck.


Conservation status: This species is not listed as endangered or threatened. Still, it is legally protected in several European countries. ∎

HERCULES BEETLE (Dynastes hercules): SPECIES ACCOUNTS

Physical characteristics: Adult males have a horn on their heads and midsections and measure 5.9 to 6.7 inches (150 to 170 millimeters) in length. The long horn on the midsection takes up to one-half of the total length. Females lack horns.


Geographic range: Hercules beetles are found in Mexico, Central America, northern South America, Guadeloupe, and the Dominican Republic.

Habitat: This species lives in humid tropical forests.


Diet: Adults eat sap and sweet fruits, while the larvae feed on rotten wood.


Behavior and reproduction: They are active at night and are often attracted to lights. Males guard feeding sites that attract hungry females. They will use their horns against other males in battles over females.


Hercules beetles and people: Some people mistakenly believe that they will become stronger and have more energy by eating the horns of the male.


Conservation status: This species is not listed as endangered or threatened. ∎

SACRED SCARAB (Scarabaeus sacer): SPECIES ACCOUNTS

Physical characteristics: The body of a sacred scarab is broad and black with a rakelike head and forelegs. They measure 0.98 to 1.2 inches (25 to 30 millimeters) in length.


Geographic range: This species is found in the Mediterranean region and central Europe.


Habitat: They live in steppe, forest-steppe, and semi-desert habitats.


Diet: Adults use their membrane-like jaws to strain fluids, molds, and other suspended particles from animal waste. The larvae eat solid waste.


Behavior and reproduction: Adult sacred scarabs fly during the day in a zig-zag pattern, following the odor of fresh animal waste. The female carves out chunks of waste with her head and legs, shapes it into a ball, and lays a single egg inside. She then stands head down and rolls the ball forward with her middle and back legs. The ball is buried and becomes the only source of food for the larva.

Sacred scarabs and people: This species recycles nutrients and destroys the breeding sites of pest flies by burying significant amounts of animal waste. Ancient Egyptians used images of the sacred scarab as a symbol of the sun god Ra. Today scarab jewelry is worn as a good luck charm.


Conservation status: This species is not listed as endangered or threatened. ∎

AMERICAN BURYING BEETLE (Nicrophorus americanus): SPECIES ACCOUNTS

Physical characteristics: Adult American burying beetles are shiny black with four wide orange spots on the elytra. The head and midsection each have a central orange spot. The tips of the antennae are also orange. They measure 0.8 to 1.4 inches (20 to 35 millimeters) in length.


Geographic range: This species was once found throughout eastern North America. It is now found only in isolated populations in the Midwest, Rhode Island, and Massachusetts.


Habitat: American burying beetles live in woodlands, grassland prairies, forest edge, and scrubland.

Diet: Both adults and larvae feed on dead animals.


Behavior and reproduction: The adults bury small, dead animals and prepare their bodies as food for themselves and their larvae. They feed and care for the larvae and remain with them until they pupate.


American burying beetles and people: Listed as an Endangered species by the World Conservation Union (IUCN), the American burying beetle symbolizes the effect of widespread habitat modification and destruction in the eastern United States.


Conservation status: This species is listed as Endangered by the World Conservation Union (IUCN) and by the United States Fish and Wildlife Service. This means it is facing a very high risk of extinction in the wild and is in danger of extinction throughout all or a significant portion of its range. ∎

DEVIL'S COACH-HORSE (Ocypus olens): SPECIES ACCOUNTS

Physical characteristics: Adult beetles are long, slender, black, and measure 0.9 to 1.3 inches (22 to 33 millimeters) in length. The body is black with short elytra exposing most of the abdominal segments.


Geographic range: This species lives in lower elevations of Europe, Russia, Turkey, North Africa, and the Canary Islands and is established in parts of North America.


Habitat: The devil's coach-horse lives in forests and gardens under stones, damp leaves, and moss, or in damp wood.


Diet: Adults and larvae prey on small, soil-dwelling arthropods, worms, slugs, and snails.


Behavior and reproduction: When threatened, the devil's coach-horse spreads its powerful jaws and bends its abdomen up over its back to spray a foul-smelling brown fluid. Nothing is known about its reproductive behavior.

Devil's coach-horses and people: This beetle was once a symbol of evil and death.


Conservation status: This species is not listed as endangered or threatened. ∎

FOR MORE INFORMATION

Books:

Evans, A. V., and C. L. Bellamy. An Inordinate Fondness for Beetles. Berkeley: University of California Press, 2000.

Evans, A. V., and J. N. Hogue. Introduction to California Beetles. Berkeley: University of California Press, 2004.

Klausnitzer, B. Beetles. New York: Exeter Books, 1983.

Lawrence, J. F., and E. B. Britton. Australian Beetles. Carlton, Australia: Melbourne University Press, 1994.

Meads, M. Forgotten Fauna: The Rare, Endangered, and Protected Invertebrates of New Zealand. Wellington, New Zealand: Department of Scientific and Industrial Research, 1990.

Tavolacci, J., editor. Insects and Spiders of the World. Volume 2: Beetle-Carpet Beetle. Volume 3: Carrion Beetle-Earwig. Volume 4: Endangered Species-Gypsy Moth. New York: Marshall Cavendish, 2003.

White, R. E. A Field Guide to the Beetles of North America. Boston: Houghton Mifflin, 1983.

Periodicals:

Cave, R. D. "Jewel Scarabs." National Geographic 199, no. 2 (2001): 52–61.

Chadwick, D. H. "Planet of the Beetles." National Geographic 193, no. 3 (1998): 1–111.

Eberhard, W. G. "Horned Beetles." Scientific American 242, no. 3 (1980): 166–182.

Evans, A. V. "Arizona's Sky Island Beetles." Reptiles Magazine 12, no. 8 (2004): 80–84.

Hadley, N. F. "Beetles Make Their Own Waxy Sunblock." Natural History 102, no. 8 (1993): 44–45.

Milne, L. J., and M. J. Milne. "The Social Behavior of Burying Beetles." Scientific American 235, no. 2 (1976): 84–89.

Web sites:

"Beetles. Coleoptera." BioKids. Critter Catalog. http://www.biokids.umich.edu/critters/information/Coleoptera.html (accessed on October 14, 2004).

"Coleoptera. Beetles, weevils." Ecowatch. http://www.ento.csiro.au/Ecowatch/Coleoptera/Coleoptera.htm (accessed on October 14, 2004).

Coleopterists Society. http://www.coleopsoc.org (accessed on October 14, 2004).

Videos:

Bug City. Aquatic Insects. Wynnewood, PA: Schlessinger Media, 1998.

Bug City. Beetles. Wynnewood, PA: Schlessinger Media, 1998.

Bug City. Ladybugs and Fireflies. Wynnewood, PA: Schlessinger Media, 1998.