Nineteen new species of Desmopachria Babington, 1841 (Coleoptera, Adephaga, Dytiscidae, Hydroporinae, Hyphydrini) with notes on the taxonomy of the genus

Nineteen new species of Desmopachria Babington, 1841 are described from multiple species groups. Two new species groups are erected, the Desmopachriaapicodente species group and the Desmopachriabifurcita species group. Desmopachriadivergenssp. nov. (Venezuela), Desmopachrialineatasp. nov. (Venezuela), Desmopachriasurinamensissp. nov. (Suriname), and Desmopachriatenuasp. nov. (Guyana) are described in Desmopachria but are not assigned to a species group. Desmopachriaapicodentesp. nov. (Guyana, Venezuela), Desmopachrialateralissp. nov. (Venezuela), and Desmopachriatumidasp. nov. (Venezuela) are described in the new Desmopachriaapicodente species group and are the only members of the group. Desmopachriabifurcitasp. nov. (Peru), and Desmopachrialatasp. nov. (Brazil) are described in the new Desmopachriabifurcita group. Other members of the Desmopachriabifurcita group are Desmopachriabifasciata Zimmermann, Desmopachriabolivari Miller, Desmopachriaovalis Sharp, and Desmopachriavarians (each previously “ungrouped”). Desmopachriapseudocaviasp. nov. (Venezuela) is described in the Desmopachriaconvexa-signata species group. Desmopachriawolfeisp. nov. (Venezuela) is described in the Desmopachrianitida species group. Desmopachriaangulatasp. nov. (Guyana, Suriname), Desmopachriaemarginatasp. nov. (Guyana, Suriname, Venezuela), Desmopachriaimparissp. nov. (Guyana), Desmopachriaimpunctatasp. nov. (Suriname, Venezuela), and Desmopachriatruncatasp. nov. (Guyana, Suriname) are described in the Desmopachriaportmanni-aldessa species group. Desmopachriabisulcatasp. nov. (Suriname), and Desmopachriairregularasp. nov. (Venezuela) are described in the Desmopachriaportmanni-portmanni species group. Desmopachriarobustasp. nov. (Venezuela) is described in the Desmopachriastriola species group. A key to the species groups is included. Male genitalia are figured for all new species and dorsal habitus images are provided for most new species.