The anostracan genus Branchinella (Crustacea: Branchiopoda), in need of a taxonomic revision; evidence from penile morphology

Abstract

Three morphologically different penile types discovered in branchmellids from Botswana are compared with literature information on congeners. The striking differences among penile structures in Branchinella ondonguae, B. ornata and the halobiontic B. spinosa raise doubts about their congeneric status. Penis morphology in B. ondonguae corresponds with the most common configuration in branchinellids, but it is largely deviant in the other two. Branchinella ornata shares penile structures with Dendrocephalus, while basal parts in B. spinosa reflect affinity with chirocephalids. A considerable general morphological variability in Branchinella, not met in any other anostracan genus, may reflect the antiquity of the group, or else poor taxonomy. Large intra-branchinellid variability and vague generic boundaries, even when considering the usually conservative penile structures, stress the need of a thorough revision of the entire family of the Thamnocephalidae. © 1997 The Linnean Society of London.