Beetles are insects that form the order Coleoptera, in the superorder Holometabola. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 described species, is the largest of all orders, constituting almost 40% of described insects and 25% of all known animal species; new species are discovered frequently, with estimates suggesting that there are between 0.9 and 2.1 million total species. 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.
The whirligig beetles are water beetles, comprising the family Gyrinidae that usually swim on the surface of the water if undisturbed, though they swim underwater when threatened. They get their common name from their habit of swimming rapidly in circles when alarmed, and are also notable for their divided eyes which are believed to enable them to see both above and below water. The family includes some 700 extant species worldwide, in 15 genera, plus a few fossil species. Most species are very similar in general appearance, though they vary in size from perhaps 3 mm to 18 mm in length. They tend to be flattened and rounded in cross section, in plain view as seen from above, and in longitudinal section. In fact their shape is a good first approximation to an ellipsoid, with legs and other appendages fitting closely into a streamlined surface. Whirligig beetles belong to the beetle suborder Adephaga, which also includes ground beetles and diving beetles.
The longhorn beetles (Cerambycidae), also known as long-horned or longicorns, are a large family of beetles, with over 35,000 species described.
The Adephaga are a suborder of beetles, and with more than 40,000 recorded species in 10 families, the second-largest of the four beetle suborders. Members of this suborder are collectively known as adephagans. The largest family is Carabidae which comprises most of the suborder with over 40,000 species. Adephaga also includes a variety of aquatic beetles, such as predaceous diving beetles and whirligig beetles.
The Elateroidea are a large superfamily of beetles. It contains the familiar click beetles, fireflies, and soldier beetles and their relatives. It consists of about 25,000 species.
Histeroidea is a superfamily of beetles in the infraorder Staphyliniformia.
Rhinorhipus is a genus of beetles that contains a single species, Rhinorhipus tamborinensis from southern Queensland, Australia. It is the sole member of the family Rhinorhipidae and superfamily Rhinorhipoidea. It is an isolated lineage not closely related to any other living beetle, estimated to have split from other beetles at least 200 million years ago, with studies either considering them the earliest diverging member of Elateriformia, or a basal lineage within Polyphaga. They exhibit feigning death (thanatosis) when disturbed. Their ecology is poorly known. It is likely that they are fossorial based on their morphology.
Andogyrus is a subgenus of Macrogyrus, a genus of beetles in the family Gyrinidae. It was formerly considered a distinct genus, until a phylogenetic study in 2017 downgraded it in rank to a subgenus. It contains the following species:
Heterogyrus milloti is a species of beetle in the family Gyrinidae, the only species in the genus Heterogyrus. It is endemic to Madagascar, and forms a basal lineage within the family, estimated to have diverged from all other gyrinids 200 million years ago. It is suggested to be closely related to the fossil genera Mesogyrus, Cretotortor and Baissogyrus which constitute the subfamily Heterogyrinae.
Gyrinus gehringi is a species of whirligig beetle in the family Gyrinidae. It is found in North America.
Gyrininae is a subfamily of ground and water beetles in the family Gyrinidae. There are at least 740 described extant species in Gyrininae.
Dineutus ciliatus is a species of whirligig beetle in the family Gyrinidae. It is found in North America.
Dineutus productus is a species of whirligig beetle in the family Gyrinidae. It is found in North America.
Dineutus emarginatus is a species of whirligig beetle in the family Gyrinidae. It is found in North America.
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 typically 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.
Chimerogyrus gigagalea is a fossil species of beetle in the family Gyrinidae, the only known species in the genus Chimerogyrus. It is known from a larval form found in Cenomanian aged Burmese amber of Myanmar. it was found to be a member of Gyrininae, sister to Dineutini + Orectochilini.
Regimbartia attenuata, commonly known as Japanese water scavenger beetle, is a species of water scavenger beetle widely distributed in the Old World, from northern Australia and Japan westward to the countries of Arabian Peninsula, including Oman and Yemen. It is the only species of the genus occurring in the Arabian Peninsula.
Porrorhynchus indicans, is a species of whirligig beetle found in Sri Lanka.
Gyrinus gibbus is a species of aquatic beetle in the family Gyrinidae. It is native to the Neotropics.
