Hydraena (Hydraenopsis): Clavicula Group

Five species are placed in this group. Members are medium sized (ca. 1.20–1.69 mm), and usually have the dorsum darkly colored and moderately coarsely punctate. There are slight differences in the plaque ratios, and the males do not have apparent sexually dimorphic legs. The aedeagus in this group is usually quite broad in lateral view, has a distal flagellum, and the parameres are short but rather broad and originate distally on the main piece. The aedeagus must be examined for reliable determinations.