Beetles are insects that form the order Coleoptera, in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 species, is the largest of all orders, constituting almost 40% of described insects and 25% of all known animal life-forms; new species are discovered frequently. The largest of all families, the Curculionidae (weevils), with some 83,000 member species, belongs to this order. Found in almost every habitat except the sea and the polar regions, they interact with their ecosystems in several ways: beetles often feed on plants and fungi, break down animal and plant debris, and eat other invertebrates. Some species are serious agricultural pests, such as the Colorado potato beetle, while others such as Coccinellidae eat aphids, scale insects, thrips, and other plant-sucking insects that damage crops.
Stag beetles are a family of about 1,200 species of beetles in the family Lucanidae, currently classified in four subfamilies. Some species grow to over 12 centimetres, but most to about 5 cm (2 in).
Ground beetles are a large, cosmopolitan family of beetles, the Carabidae, with more than 40,000 species worldwide, around 2,000 of which are found in North America and 2,700 in Europe. As of 2015, it is one of the 10 most species-rich animal families.
The insects of the beetle family Chrysomelidae are commonly known as leaf beetles, and include over 37,000 species in more than 2,500 genera, making up one of the largest and most commonly encountered of all beetle families. Numerous subfamilies are recognized, but the precise taxonomy and systematics are likely to change with ongoing research.
The rove beetles are a family (Staphylinidae) of beetles, primarily distinguished by their short elytra that typically leave more than half of their abdominal segments exposed. With roughly 63,000 species in thousands of genera, the group is currently recognized as the largest extant family of organisms. It is an ancient group, with fossilized rove beetles known from the Triassic, 200 million years ago, and possibly even earlier if the genus Leehermania proves to be a member of this family. They are an ecologically and morphologically diverse group of beetles, and commonly encountered in terrestrial ecosystems.
The longhorn beetles (Cerambycidae), also known as long-horned or longicorns, are a large family of beetles, with over 35,000 species described, slightly more than half from the Eastern Hemisphere. Most species are characterized by extremely long antennae, which are often as long as or longer than the beetle's body. In various members of the family, however, the antennae are quite short and such species can be difficult to distinguish from related beetle families such as the Chrysomelidae. The scientific name of this beetle family goes back to a figure from Greek mythology: after an argument with nymphs, the shepherd Cerambus was transformed into a large beetle with horns.
Dung beetles are beetles that feed on feces. Some species of dung beetles can bury dung 250 times their own mass in one night.
Polyphaga is the largest and most diverse suborder of beetles. It comprises 144 families in 16 superfamilies, and displays an enormous variety of specialization and adaptation, with over 350,000 described species, or approximately 90% of the beetle species so far discovered.
Darkling beetle is the common name of the large family of beetles Tenebrionidae. The number of species in the Tenebrionidae is estimated at more than 20,000 and the family is cosmopolitan in distribution.
Buprestidae is a family of beetles known as jewel beetles or metallic wood-boring beetles because of their glossy iridescent colors. Larvae of this family are known as flatheaded borers. The family is among the largest of the beetles, with some 15,500 species known in 775 genera. In addition, almost 100 fossil species have been described.
The Dytiscidae – based on the Greek dytikos (δυτικός), "able to dive" – are the predaceous diving beetles, a family of water beetles. They occur in virtually any freshwater habitat around the world, but a few species live among leaf litter. The adults of most are between 1 and 2.5 cm (0.4–1.0 in) long, though much variation is seen between species. The European Dytiscus latissimus and Brazilian Megadytes ducalis are the largest, reaching up to 4.5 cm (1.8 in) and 4.75 cm (1.9 in) respectively. In contrast, the smallest is likely the Australian Limbodessus atypicali of subterranean waters, which only is about 0.9 mm (0.035 in) long. Most are dark brown, blackish, or dark olive in color with golden highlights in some subfamilies. The larvae are commonly known as water tigers due to their voracious appetite. They have short, but sharp mandibles and immediately upon biting, they deliver digestive enzymes into prey to suck their liquefied remains. The family includes more than 4,000 described species in numerous genera.
Histeridae is a family of beetles commonly known as clown beetles or Hister beetles. This very diverse group of beetles contains 3,900 species found worldwide. They can be easily identified by their shortened elytra that leaves two of the seven tergites exposed, and their geniculate (elbowed) antennae with clubbed ends. These predatory feeders are most active at night and will fake death if they feel threatened. This family of beetles will occupy almost any kind of niche throughout the world. Hister beetles have proved useful during forensic investigations to help in time of death estimation. Also, certain species are used in the control of livestock pests that infest dung and to control houseflies. Because they are predacious and will even eat other Hister beetles, they must be isolated when collected.
The Cucujidae, "flat bark beetles," are a family of distinctively flat beetles found worldwide under the bark of dead trees. The family has received considerable taxonomic attention in recent years and now consists of 59 species distributed in four genera. It was indicated Cucujus species are scavengers, only feeding on pupae and larvae of other insects and on other subcortical beetles such as their own. Since the Cucujidae prey on larvae of potentially tree damaging beetles that spread fungal diseases, they are considered to be beneficial to the health of living trees.
A bark beetle is one of about 6,000 species in 247 genera of beetles in the subfamily Scolytinae. Previously, this was considered a distinct family (Scolytidae), but is now understood to be a specialized clade of the "true weevil" family (Curculionidae). Although the term "bark beetle" refers to the fact that many species feed in the inner bark (phloem) layer of trees, the subfamily also has many species with other lifestyles, including some that bore into wood, feed in fruit and seeds, or tunnel into herbaceous plants. Well-known species are members of the type genus Scolytus, namely the European elm bark beetle S. multistriatus and the large elm bark beetle S. scolytus, which like the American elm bark beetle Hylurgopinus rufipes, transmit Dutch elm disease fungi (Ophiostoma). The mountain pine beetle Dendroctonus ponderosae, southern pine beetle Dendroctonus frontalis, and their near relatives are major pests of conifer forests in North America. A similarly aggressive species in Europe is the spruce ips Ips typographus. A tiny bark beetle, the coffee berry borer, Hypothenemus hampei is a major pest on coffee plantations around the world.
Prostomidae is a family of beetles with no vernacular common name, though recent authors have coined the name jugular-horned beetles. They are often found in dead wood. The family consist of two genera with about 20 species. Prostomis mandibularis is known from North America. Other species of Prostomis are found in Africa, the Pacific region and East Asia. Species of Dryocora are known from New Zealand, Australia and Tasmania.
Cleridae are a family of beetles of the superfamily Cleroidea. They are commonly known as checkered beetles. The family Cleridae has a worldwide distribution, and a variety of habitats and feeding preferences.
Coccinellidae is a widespread family of small beetles ranging in size from 0.8 to 18 mm. The family is commonly known as ladybugs in North America and ladybirds in Great Britain and other parts of the English-speaking world. Entomologists prefer the names ladybird beetles or lady beetles as these insects are not classified as true bugs.
Chlaenius is a large and diverse genus of ground beetle. It is native to the Palearctic realm, Afrotropical realm, and Nearctic realm. Worldwide, roughly 1,000 species are currently recognized with the majority of known species occurring in the Oriental and Afrotropical regions. The genus is divided into many subgenera.
Jacobsoniidae is a family of beetles. The larvae and adults live under bark, in plant litter, fungi, bat guano and rotten wood. It is a small family with 23 described species in three genera:
Copelatinae is a subfamily of diving beetles, in the family Dytiscidae. The subfamily contains seven genera: Agaporomorphus, Aglymbus, Copelatus, Exocelina, Lacconectus, Liopterus, and Madaglymbus. Of these, the largest is Copelatus, which has about 470 described species found worldwide, but most diverse in tropical South America, Africa and South-East Asia.
