Hydraena costiniceps

Perkins, Philip D., 2011, New records and description of fifty-four new species of aquatic beetles in the genus Hydraena Kugelann from South America (Coleoptera: Hydraenidae), Zootaxa 3074, pp. 1-198 : 24

Costiniceps Complex

Ten species are included in the Costiniceps Complex: H. costiniceps , H. cherylbarrae , H. buscintilla , H. scintillapicta , H. mintrita , H. amazonica , H. scintillamima , H. scintillarca , H. nanoscintilla , and H. colombiana . These are medium sized species (ca. 1.25–1.51 mm), which have a large pronotal scintilla. The pronotum has a macula or fascia in some species, but is dark, unicolorous in others. The male genitalia are stout in this complex, and have a basic plan similarity, with the main-piece, distal piece, and parameres together forming a more or less cup shape; the gonopore bearing flagellum is short and 'inside' the cup (e.g., Figs. 25–26).