The genus Argulus (Crustacea: Branchiura) in Africa: two new species, A. fryeri and A. gracilis, the previously undescribed male of A. brachypeltis Fryer and the identity of the male described as A. ambloplites Wilson. Systematic Parasitology, 28(1), May 1994: 23-31. 24 [Zoological Record Volume 131]