Spercheus is a genus of aquatic beetles which are placed in a family of their own, Spercheidae within the Hydrophiloidea. About 20 species are known from around the world except the Nearctic with the majority being from the Oriental and Afrotropical Realms.
The Hydroscaphidae are a small family of water beetles known commonly as skiff beetles. As of 2010, there are 23 species in the family. Several are recently described.
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.
Carabdytes alutaceus is an endangered species of beetle in the family Dytiscidae. It is endemic to New Caledonia, in the southwest Pacific Ocean.
Meridiorhantus orbignyi is an extinct species of predaceous diving beetle in the family Dytiscidae. This species was formerly a member of the genus Rhantus.
Tenomerga is a genus of beetles in the family Cupedidae. This genus has about 17 extant species, which are native to the eastern Palearctic, Nearctic and Oriental regions.
Carabdytes is a genus of predaceous diving beetles in the family Dytiscidae. Carabdytes upin was formerly the sole species of this genus, but nine species in the genus Rhantus were transferred to Carabdytes as a result of research published by Balke et al. in 2017.
Celadonia is a genus of beetles in the family Callirhipidae. It was described by Laporte de Castelnau in 1840.
Ennometes is a genus of beetles in the family Callirhipidae. It was described by Pascoe in 1866.
Meridiorhantus calidus is a species of predaceous diving beetle in the family Dytiscidae. It is found in North America and the Neotropics. This species was formerly a member of the genus Rhantus.
Aspidytes is a genus of aquatic beetles in the family Aspidytidae, first recorded in 2002 from specimens in South Africa. The genus contains the single species Aspidytes niobe. Originally a second species from China was placed in the same genus but has later been transferred to Sinaspidytes. The aquatic beetle is 6.5 - 7.2 mm long and lives in hygropetric habitats.
Carabdytes plantaris is a naturally uncommon species of diving beetle in the family Dytiscidae. It is endemic to New Zealand. For over a century, it was known from just a single specimen collected in 1880 "near Dunedin", and doubts were cast on whether it was actually a New Zealand species at all. In 1986, it was rediscovered when several were collected from a roadside pond near Lake Ellesmere. Carabdytes plantaris is now classed as "naturally uncommon" by the Department of Conservation.
Nartus grapii is a species of beetle in family Dytiscidae, found in the Palearctic. This species was formerly a member of the genus Rhantus.
Nartus sinuatus Black with dark rufous legs; posterior margin of pronotum arched just before hind angles(3) is a species of predaceous diving beetle in the family Dytiscidae, found in North America. This species was formerly a member of the genus Rhantus.
Epimetopidae is a family of semi-aquatic beetles belonging to the Hydrophiloidea. They are found in sand and gravel at the edges of streams, rivers and shallow freshwater ponds. These beetles are shorter than half a centimeter long and have a pronotum with a central projection forming a shelf above the head. On the underside of the abdomen only four sternites are visible. There are approximately 72 described species in three genera, Epimetopus which is restricted to the New World, mostly Neotropical, Eupotemus with two Afrotropical species and Eumetopus with some Oriental species. Females carry their eggcases on the underside of the abdomen. The larvae are probably carnivorous based on their mouthparts and likely live in the same habitats as the adults.
Aspidytidae is a family of aquatic beetles of the suborder Adephaga, described in 2002 from specimens in South Africa and China. There are only two known species in the family and these were originally described in the genus Aspidytes, but later the new genus Sinaspidytes was erected for the species found in China. The family can also be referred to by its trivial name cliff water beetles.
Meridiorhantus is a genus of predaceous diving beetles in the family Dytiscidae. There are about five described species in Meridiorhantus, found in the Neotropics and North America. These species were formerly members of the genus Rhantus, but were moved to Meridiorhantus when it was created by Balke et al. in 2017.
Caperhantus is a genus of predaceous diving beetles in the family Dytiscidae. There is one described species in Caperhantus, C. cicurius. This species was formerly a member of the genus Rhantus.
Nartus is a genus of predaceous diving beetles in the family Dytiscidae. There are at least two described species in Nartus. These species were formerly members of the genus Rhantus, but were moved to Nartus when it was reinstated by Balke et al. in 2017.
Coelostoma (Coelostoma) vitalisi, is a species of water scavenger beetle found in China, Taiwan, Japan, India, Indonesia, Japan, Malaysia, Nepal, Singapore, Sri Lanka, Cambodia, Thailand and Vietnam.
