Myxophaga is the second-smallest suborder of the Coleoptera after Archostemata, consisting of roughly 65 species of small to minute beetles in four families. The members of this suborder are aquatic and semiaquatic, and feed on algae.
Colydiinae is a subfamily of beetles, commonly known as cylindrical bark beetles. They have been treated historically as a family Colydiidae, but have been moved into the Zopheridae, where they constitute the bulk of the diversity of the newly expanded family, with about 140 genera worldwide. They are diverse for example in the Australian region, from where about 35 genera are known; in Europe, though, only 20 genera are found and many of these only with few species.
Ripiphoridae is a cosmopolitan family of some 450 described species of beetles sometimes called "wedge-shaped beetles". Ripiphoridae are unusual among beetle families in that many species are hypermetamorphic parasitoids, an attribute that they share with the Meloidae. Members of the family differ in their choice of hosts, but most attack various species of bees or wasps, while some others attack cockroaches or beetles. Many species of Ripiphoridae have abbreviated elytra, and flabellate or pectinate antennae.
Corylophidae is a family of minute hooded beetles, sometimes called minute fungus beetles, in the superfamily Coccinelloidea. There are about 18 genera and at least 120 described species in Corylophidae. They feed on microfungi such as molds, and are often found associated with bark, as well as in leaf litter and other decaying vegetation. In older literature, the family name was often given as Orthoperidae.
Jacobsoniidae are a family of tiny beetles belonging to Staphylinoidea. The larvae and adults live under bark, in plant litter, fungi, bat guano and rotten wood. There are around 28 described species in three genera:
Boganiidae is a family of beetles, in the superfamily Cucujoidea. Members of the family are found in southern Africa, Australia and New Caledonia. Adults and larvae are pollenivorous, feeding on the pollen of cycads and flowering plants of the families Myrtaceae, Meliaceae, Cunoniaceae and Elaeocarpaceae. Metacucujus and Paracucujus act as pollinators for cycads Encephalartos and Macrozamia respectively. This association with cycads goes back to at least the Mid-Cretaceous, with an extinct form being found with preserved cycad pollen in 99 million year old Burmese amber.
Bothrideridae is a family of beetles in the superfamily Coccinelloidea. They are known commonly as the cocoon-forming beetles or dry bark beetles. They occur worldwide with most native to the Old World tropics. In older literature, the family was often included in the family Colydiidae, but is now considered unrelated.
Silvanidae, "silvan flat bark beetles", is a family of beetles in the superfamily Cucujoidea, consisting of 68 described genera and about 500 described species. The family is represented on all continents except Antarctica, and is most diverse at both the generic and species levels in the Old World tropics.
Passandridae, the "parasitic flat bark beetles," are a family of beetles notable for being one of the very few beetle families with larvae that are, as far as known, exclusively ectoparasitic on the immature stages of other beetles and Hymenoptera.
Coccinelloidea is a superfamily of beetles in the order Coleoptera, formerly included in the superfamily Cucujoidea. There are more than 10,000 species in Coccinelloidea, including more than 6000 in the lady beetle family Coccinellidae.
Scymninae is a subfamily of beetles in the family Coccinellidae. There are at least 170 described species in Scymninae.
Gyrininae is a subfamily of ground and water beetles in the family Gyrinidae. There are at least 740 described extant species in Gyrininae.
Murmidiidae is a family of beetles in the superfamily Coccinelloidea, formerly included within the family Cerylonidae. The family contains thirty-four described species in four genera, which are found worldwide. They are typically found under the bark of recently dead trees, and are thought to be mycophagous. The species Murmidius ovalis, found worldwide, is noted as a pest of stored food.
Anamorphidae is a family of beetles in the superfamily Coccinelloidea, formerly included within the family Endomychidae. They are found worldwide. Like enchomyids, they are fungivores, with adult and larval stages thought to exclusively consume fungal spores.
Eupsilobiidae is a family of beetles in the superfamily Coccinelloidea, formerly included within the family Endomychidae. Most genera are restricted to the Neotropics, while the genus Eidoreus is found worldwide. They are fungivores, and have been observed living commensally in bee and ant nests.
Limnichidae, commonly called minute marsh-loving beetles, is a family of beetles belonging to Byrrhoidea. There are at least 30 genera and 350 described species in Limnichidae. They are found worldwide, with the greatest diversity in tropical regions. Most species seem to be associated with water-adjacent habitats, such as riparian and coastal locations, though many species are likely fully terrestrial, with some species being associated with leaf litter and arboreal habitats. Species with known diets feed on moss or algae. The oldest fossils of the family are known from mid-Cretaceous Burmese amber from Myanmar.
Ptilodactylidae is a family of beetles belonging to the Elateriformia. There around 500 extant species in 35 genera. They are generally associated with riparian and aquatic habitats. The larvae generally live associated with rotting wood or vegetation, or within gravel and detritus on the edge of water bodies. The larvae of some species feed on submerged rotting wood or on plant roots, while the adults of some species are known to feed on fungus with modified brush-like maxillae.
Artematopodidae is a family of soft-bodied plant beetles in the superfamily Elateroidea. They are mostly found in understory forest foliage. The life history of the group is obscure, larvae of the genera Eurypogon and Macropogon likely feed on moss, while the larvae of Artematopus have been fed insect remains.The oldest fossils of the family date to the Middle Jurassic.
Cyclaxyridae are a family of beetles in the superfamily Cucujoidea. The only living genus is Cyclaxyra, with two species endemic to New Zealand. Other species have been named from fossils. They are also known as sooty mould beetles due to the association of Cyclaxyra with sooty mould. The extant species are mycophagous, feeding on spores, conidia, and hyphae.
Burmese amber is fossil resin dating to the early Late Cretaceous Cenomanian age recovered from deposits in the Hukawng Valley of northern Myanmar. It is known for being one of the most diverse Cretaceous age amber paleobiotas, containing rich arthropod fossils, along with uncommon vertebrate fossils and even rare marine inclusions. A mostly complete list of all taxa described up until 2018 can be found in Ross 2018; its supplement Ross 2019b covers most of 2019.
