(Redirected from Hydrochidae)

Hydrochus is a genus of water scavenger beetles in the monogeneric family Hydrochidae, sometimes placed in the Hydrophilidae as a subfamily Hydrochinae. The family Hydrochidae includes about 180 species, all of which are placed in the genus Hydrochus. Hydrochus has also been used for a fly genus in the family Dolichopodidae. This junior homonym is a junior subjective synonym of the genus Rhaphium.

Hydrochus P1310411a.jpg
Scientific classification e
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Coleoptera
Infraorder: Staphyliniformia
Superfamily: Hydrophiloidea
Family: Hydrochidae
Thomson, 1859
Genus: Hydrochus
Leach, 1817

Kiransus Makhan, 1994

Beetles in the genus Hydrochus are found in slow moving streams or stagnant water bodies. The club of the 7 segmented antenna consists of three segments with a cup-like basal segment. The number of tarsi on the legs are usually 5-5-5 or 4-4-4 (a tiny basal segment can be hard to see). The pronotum narrows towards the rear but is narrower than the base of the elytra. They walk around inside water or swim weakly in search of invertebrate prey. They hold air under the elytra. The larvae are also aquatic and predatory. An African species was formerly described under the genus Kiransus, but along with several other African species, they are now placed in Hydrochus.[1] Hydrochids are considered to be an older branch of the Hydrophiloidea. Hydrochids have been suggested as a sister group of the Spercheidae+Hydrophilidae but the relationships are unclear. Molecular phylogenetic comparisons suggest that they are related as a sister group to Helophorus+Georissus.[2]

An extinct member of the family, Ponohydrochus is known from the Early Cretaceous (Hauterivian) Khasurty locality in Russia.[3]

Hydrochus P1310412a.jpg
Hydrochus P1120860a.jpg


More than 180 species have been described in the genus. The following list includes some of the species in the genus:[4]

Data sources: i = ITIS,[6] c = Catalogue of Life,[7] g = GBIF,[8] b = Bugguide.net[9]


  1. ^ Hansen, M. (1998). "The systematic status of Kiransus Makhan, 1994, with the description of three new species of Hydrochus Leach, 1817 (Coleoptera: Hydrochidae)". Insect Systematics & Evolution. 29 (2): 223–232. doi:10.1163/187631298x00302.
  2. ^ Short, Andrew Edward Z.; Fikáček, Martin (2013). "Molecular phylogeny, evolution and classification of the Hydrophilidae (Coleoptera): Classification of the Hydrophilidae". Systematic Entomology. 38 (4): 723–752. doi:10.1111/syen.12024.
  3. ^ Prokin, A. A.; Strelnikova, O. D. (2021). "The first remarkable fossil Hydrochidae (Coleoptera) from the Lower Cretaceous (Hauterivian) of the Buryatia Republic, Russia". Cretaceous Research. 123: 104795. doi:10.1016/j.cretres.2021.104795. ISSN 0195-6671.
  4. ^ Hidalgo-Galiana, A.; Ribera, I. (2011). "Late Miocene diversification of the genus Hydrochus (Coleoptera, Hydrochidae) in the west Mediterranean area". Molecular Phylogenetics and Evolution. 59 (2): 377–385. doi:10.1016/j.ympev.2011.01.018. PMID 21354316.
  5. ^ a b Worthington, Reese J.; Hellman, John L.; Lago, Paul K. (2016). "Hydrochidae (Coleoptera) of Mississippi". Transactions of the American Entomological Society. 142 (2): 167–213. doi:10.3157/061.142.0206. S2CID 88919765.
  6. ^ "Hydrochus Report". Integrated Taxonomic Information System. Retrieved 2018-04-22.
  7. ^ "Browse Hydrochus". Catalogue of Life. Retrieved 2018-04-22.
  8. ^ "Hydrochus". GBIF. Retrieved 2018-04-22.
  9. ^ "Hydrochus Genus Information". BugGuide.net. Retrieved 2018-04-22.