Hydraena, Kugelann

PERKINS, PHILIP D., 2014, A revision of the water beetle genus Hydraena Kugelann for southern Africa (Coleoptera: Hydraenidae), Zootaxa 3758 (1), pp. 1-92 : 73

Hydraena (incertae sedis): Monikae Group

Four species are placed in this group; members distinctively differ from other southern African Hydraena in some basic morphological characters of the venter: 1) the genae are raised and have a posterior ridge; 2) the mesoventral intercoxal process has the sides tapering to a narrow apex; 3) the abdominal intercoxal sternite is subtriangular and deeply concave; and 4) females have the gonocoxite midlongitudinally divided. In addition, the male genitalia have a distinctive form, tubular and markedly arcuate, with a terminal flagellum and with short parameres. These species appear not to be members of Hydraena (Hydraenopsis) , and perhaps represent an undescribed subgenus that may be related to some South American groups, namely the Paeminosa, Curvosa, and Multispina Groups, which have some similar characters ( Perkins 2011).