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.
Copelatus proximus is a species of diving beetle. It is part of the genus Copelatus of the subfamily Copelatinae and the family Dytiscidae. It was described by Sharp in 1882.
Copelatus restrictus is a species of diving beetle. It is part of the genus Copelatus of the subfamily Copelatinae and the family Dytiscidae. It was described by Sharp in 1882.
Berosus is a genus of beetles in the family Hydrophilidae, the water scavenger beetles. The genus contains 273 species. It is distributed worldwide.
Deltostethus is a genus of water scavenger beetles in the family Hydrophilidae. There are at least four described species in Deltostethus.
Hyphydrini is a tribe of predaceous diving beetles in the family Dytiscidae. There are about 16 genera and more than 390 described species in Hyphydrini.
Pycnomerus is a genus of ironclad beetles in the family Zopheridae. There are more than 20 described species in Pycnomerus.
Chaetarthria is a genus of water scavenger beetles in the family Hydrophilidae. There are more than 20 described species in Chaetarthria.
Hexacylloepus is a genus of riffle beetles in the family Elmidae. There are about 19 described species in Hexacylloepus.
Phanocerus is a genus of riffle beetles in the family Elmidae. There are about seven described species in Phanocerus.
Dactylosternum is a genus of water scavenger beetles in the family Hydrophilidae. There are more than 20 described species in Dactylosternum.
Coelostomatini is a tribe of water scavenger beetles in the family Hydrophilidae. There are about 7 genera and more than 70 described species in Coelostomatini.
Pelosoma is a genus of water scavenger beetles in the family Hydrophilidae. There are about seven described species in Pelosoma.
Halobrecta is a genus of rove beetles in the family Staphylinidae. There are about six described species in Halobrecta.
Laccophilus oscillator is a species of predaceous diving beetle in the family Dytiscidae. It is found in North America and the Neotropics.
Neocylloepus is a genus of riffle beetles in the family Elmidae. There are about eight described species in Neocylloepus.
Pelonomus is a genus of long-toed water beetles in the family Dryopidae. There are about five described species in Pelonomus.
Phaenonotum is a genus of water scavenger beetles in the family Hydrophilidae. There are about nine described species in Phaenonotum.
Cryptopleurum is a genus of water scavenger beetles in the family Hydrophilidae. There are about 11 described species in Cryptopleurum.
