Parhydraenopsis, Perkins, 2009

Perkins, Philip D., 2009, Revisions of the genera Parhydraena Orchymont, Protozantaena Perkins, Decarthrocerus Orchymont, and Parhydraenopsis nomen novum, aquatic and humicolous beetles from Africa and Madagascar, and comparative morphology of the tribe Parhydraenini (Coleoptera: Hydraenidae), Zootaxa 2038, pp. 1-119 : 13

Key to species of Parhydraenopsis

1 Elytra comparatively narrow, width/length ratio ca. 0.66; pronotum less explanate; smaller species, length ca. 2.12 mm; aedeagus as illustrated ( Figs. 82, 83) ........................................................................................... simiensis n. sp.

- Elytra broader, width/length ratio ca. 0.72–0.74; metaventral disc with shallow median elongate impression; larger species, length ca. 2.34–2.38 mm ................................................................................................................................. 2

2 Legs longer and pronotum less explanate, metatibia+metatarsus length subequal width of pronotum; maxillary palpi comparatively longer, palpus length/head width ratio ca. 0.57; aedeagus as illustrated ( Figs. 78, 80) ......................... ....................................................................................................................................................... cooperi (Orchymont)

- Legs shorter and pronotum more explanate, metatibia+metatarsus length much less than width of pronotum; maxillary palpi comparatively shorter, palpus length/head width ratio ca. 0.42; aedeagus as illustrated ( Figs. 79, 81) ......................................................................................................................................................................... alta n. sp.