Thirty-three new species of water beetles in the genus Hydraena Kugelann from Cameroon (Coleoptera: Hydraenidae)

Thirty-three new species of Cameroonian water beetles in the genus Hydraena Kugelann are described, based on the examination and databasing of 355 specimens from 19 localities/events. Male genitalia are illustrated, and high resolution habitus images of the holotypes are provided, as are distribution maps. The following new species of Hydraena are described: H. cameroancylis, H. cameroarida, H. camerobuloba, H. camerocameola, H. camerocarinata, H. cameroclandestina, H. camerocompacta, H. camerocomplexa, H. camerocompressa, H. cameroconcava, H. cameroconfinis, H. camerocontinua, H. camerocontrasta, H. cameroconvexa, H. camerocordata, H. camerocorona, H. camerocrebrata, H. camerocubita, H. camerocurvata, H. camerodidacta, H. camerodigita, H. cameroflagellata, H. camerofoveata, H. camerojocula, H. camerolatula, H. cameroovala, H. cameropalmula, H. cameropetila, H. cameroradiata, H. camerosemicordata, H. camerosetosa, H. camerosicula, and H. millenaria.

Automated summary

Thirty-three new species of the genus Hydraena Kugelann, Cameroonian water beetles, are described in this article. The descriptions and classifications are based on the examination and databasing of 355 specimens from 19 localities/events. The article includes illustrations of male genitalia, high resolution images of holotypes, and distribution maps.