 It includes the genera "Baciliometra" (Esaki), with four species from tropical South America, "Chaetometra" (Hungerford) and "Dolichocephalometra" (Hungerford), two monotypic genera from the Marquesas Islands, and "Hydrometra", of at least 80 species worldwide and all North American species.The final subfamily is Limnobatodinae, which is closely related to Hydrometrinae, although it has hairs only on its head, thorax, and base of the abdomen, and pronotum longer than the ante-ocular portion of its head.It comprises a single species, "Limnobatodes paradoxus" (Hussey), from Belize, Brazil and Peru .