A New, Sexually Dimorphic Species of Cylloepus Erichson from Brazil (Coleoptera: Elmidae)

Cylloepus dimorphus Shepard, Sites, and Rodrigues, new species (Elmidae) is described from Brazil with a sexually dimorphic abdominal ventrite 5. Males have a protruding lobe on each side of the apex of ventrite 5. Females lack the lobes and are not distinguishable from congeners.