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.
Hydroporus compunctus is a species of predaceous diving beetle in the family Dytiscidae. It is endemic to the Canary Islands.
Hydroporus pilosus is a species of predaceous diving beetle in the family Dytiscidae. It is endemic to the Canary Islands.
Hydroporus erythrocephalus is a species of predaceous diving beetle in the family Dytiscidae. It is found in the Palearctic, including Europe and the Near East.
Hydroporus pubescens is a species of predaceous diving beetle in the family Dytiscidae. It is found in the Palearctic.
Ilybius chalconatus is a species of predaceous diving beetle in the family Dytiscidae. It is found in the Palearctic.
Hoperius is a genus of predaceous diving beetles in the family Dytiscidae. This genus has a single species, Hoperius planatus. It is found in the United States east of the Rocky Mountains.
Austrodytes is a genus of beetles in the family Dytiscidae found only in northern Australia. It was first described in 1978 by Chris Watts. The genus contains these two species:
Regimbartina is a genus of predaceous diving beetles in the family Dytiscidae. This genus has a single species, Regimbartina pruinosa.
Microdessus is a genus of predaceous diving beetles in the family Dytiscidae. This genus has a single species, Microdessus atomarius, found in Brazil.
Sinodytes is a genus of predaceous diving beetles in the family Dytiscidae. This genus has a single species, Sinodytes hubbardi, found in southern Asia.
Andex is a genus of predaceous diving beetles in the family Dytiscidae. This genus has a single species, Andex insignis.
Darwinhydrus is a genus of predaceous diving beetles in the family Dytiscidae. This genus has a single species, Darwinhydrus solidus, found in South Africa.
Dimitshydrus is a genus of predaceous diving beetles in the family Dytiscidae. This genus has a single species, Dimitshydrus typhlops. It is found in southern Asia.
Japanolaccophilus is a genus of predaceous diving beetles in the family Dytiscidae. There are at least two described species in Japanolaccophilus, one alive today and the other extinct.
Agabinus is a genus of predaceous diving beetles in the family Dytiscidae. There are at least two described species in Agabinus. They are found in North America.
Acilius fraternus is a species of predaceous diving beetle in the family Dytiscidae. It is found in North America.
Hydroporus pervicinus is a species of predaceous diving beetle in the family Dytiscidae. It is found in North America.
Cybistrini is a tribe of predaceous diving beetles in the family Dytiscidae. There are 7 genera and 128 described extant species in Cybistrini. The same set is also called Cybistrinae by authors viewing it as a subfamily of Dytiscidae.
Acilius semisulcatus is a species of predaceous diving beetle in the family Dytiscidae. It is found in North America.
