Beetles are a group of 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 is 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).
Spercheus is a genus of aquatic beetles which are placed in a family of their own, Spercheidae. About 20 species are known from around the world, with the majority being from the Oriental and Afrotropical Realms.
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.
Amphizoa is a genus of aquatic beetles in the suborder Adephaga, placed in its own monogeneric family, Amphizoidae. There are five known species of Amphizoa, three in western North America and two in eastern palearctic. They are sometimes referred to by the common name troutstream beetles.
Elateriformia is an infraorder of polyphagan beetles. The two largest families in this group are buprestids, of which there are around 15,000 described species, and click beetles, of which there are around 10,000 described species.
The Lymexylidae, also known as ship-timber beetles, are a family of wood-boring beetles. Lymexylidae belong to the suborder Polyphaga and are the sole member of the superfamily Lymexyloidea.
Pselaphinae are a subfamily of beetles in the family Staphylinidae, the rove beetles. The group was originally regarded as a separate family named Pselaphidae. Newton and Thayer (1995) placed them in the Omaliine group of the family Staphylinidae based on shared morphological characters.
Staphylinoidea is a superfamily of beetles. It is a very large and diverse group with worldwide distribution.
The Rhagophthalmidae are a family of beetles within the superfamily Elateroidea. Members of this beetle family have bioluminescent organs on the larvae, and sometimes adults, and are closely related to the Phengodidae, though historically they have been often treated as a subfamily of Lampyridae, or as related to that family. Some recent evidence suggested that they were the sister group to the Phengodidae, and somewhat distantly related to Lampyridae, whose sister taxon was Cantharidae, but more reliable genome-based phylogenetics placed as the sister group to the Lampyridae.
Dolichopodidae, the long-legged flies, are a large, cosmopolitan family of true flies with more than 7,000 described species in about 230 genera. The genus Dolichopus is the most speciose, with some 600 species.
Histeroidea is a superfamily of beetles in the infraorder Staphyliniformia.
Syntelia is a genus of middle-sized beetles described by John O. Westwood in 1864. It is the only genus in the family Synteliidae erected by George Lewis in 1882.
Agyrtidae, or primitive carrion beetles, are a small family of polyphagan beetles They are found in mostly temperate areas of the northern hemisphere and in New Zealand. They feed on decaying organic material.
Georissus, also called minute mud-loving beetles, is the only genus in the beetle family Georissidae. They are tiny insects living in wet soil, often near water. Found on every continent except Antarctica.
Helophorus ís the only genus in the beetle family Helophoridae. They are small insects, found mainly in the Holarctic region, but two or three species also live in the Afrotropical region, Central America and one in the Indomalayan region.
Hygrobia is a genus of aquatic beetles native to Europe, North Africa, China and Australia. It is the only genus in the family Hygrobiidae, also known as the Paelobiidae. These are known commonly as squeak beetles or screech-beetles.
Hister is a genus of clown beetles in the family Histeridae. There are at least 210 described species in Hister.
Phytophaga is a clade of beetles within the infraorder Cucujiformia consisting of the superfamilies Chrysomeloidea and Curculionoidea that are distinctive in the plant-feeding habit combined with the tarsi being pseudotetramerous or cryptopentamerous, where the fourth tarsal segment is greatly reduced or hidden by the third tarsal segment. The Cucujoidea are a sister to the Phytophaga. In some older literature the term Phytophaga was applied only to the Chrysomeloidea.
