Acilius (beetle)

Acilius is a holarctic genus of diving beetles in the family Dytiscidae and typically has a life cycle that is univoltine.

Despite the prevalence of some species, one species, A. duvergeri, is listed as vulnerable on the IUCN Red List.

Species
The genus Acilius contains the following 13 extant species in 2 subgenera:

Subgenus Acilius: Subgenus Homoelytrus
 * Acilius abbreviatus Aubé, 1838
 * Acilius athabascae Larson, 1975
 * Acilius canaliculatus (Nicolai, 1822)
 * Acilius confusus Bergsten, 2006
 * Acilius fraternus (Harris, 1828)
 * Acilius japonicus Brinck, 1939
 * Acilius kishii Nakane, 1963
 * Acilius mediatus (Say, 1823)
 * Acilius semisulcatus Aubé, 1838
 * Acilius sinensis Peschet, 1915
 * Acilius sulcatus (Linnaeus, 1758)
 * Acilius sylvanus Hilsenhoff, 1975
 * Acilius duvergeri Gobert, 1874

Extinct species
These three extinct species are known only from fossils:
 * †Acilius florissantensis Wickham, 1909
 * †Acilius oeningensis (Heer, 1847)
 * †Acilius praesulcatus Lomnicki, 1894