Two new species of Desmopachria Babington, 1841 in the D. convexa species group (Coleoptera, Adephaga, Dytiscidae, Hydroporinae, Hyphydrini)

Two new species are described in the Desmopachria convexa species group in the Neotropical genus Desmopachria Babington: D. mancosp. nov. (Guyana), and D. mortimersp. nov. (Costa Rica). Two subgroups, the D. convexa-convexa and the D. convexa-signata groups are defined. Desmopachria convexa-convexa species are from North and Central America and have a subapical articulable lobe on the male lateral lobe that is large and elongate and extends well beyond the slender, oblique apex of the lateral lobe. Desmopachria convexa-signata species are from South America and have a subapical articulable lobe on the male lateral lobe that is small and discrete and does not extend beyond the truncate apex of the lateral lobe. The male genitalia of all recognized species in the D. convexa group are redrawn from the literature. New species are illustrated from specimens and described species have morphological features redrawn from published illustrations.