Some Ultrastructural Aspects of Spermatogenesis and Sperm Morphology in the Brine Shrimp Artemia salina Leach (Crustacea: Branchiopoda)

Although crustacean diversity has stimulated research enormously, sperm morphology and functional aspects have received little attention recently as compared to earlier times (e.g., Gilson, 1886; Retzius, 1909; Wilson, 1928). The exceptions include primarily the malacostracan spermatozoa (e.g., isopods, Reger, 1964; decapods, Moses, 1961; Brown, 1966a; Anderson and Ellis, 1967; Chevaillier, 1966, 1967; Vaughn, 1968), although other representatives have also been studied (e.g., Branchiopods, Fautrez-Firlefyn, 1951; Fautrez-Firlefyn and Fautrez, 1954, 1955; Ostracods, Lowndes, 1935). In recent studies, the author (Brown, 1966a, 1966b; Brown and Metz, 1967) has examined spermatozoa of representative species of seven crustacean subclasses (Ostracoda excepted). These studies involved the comparison of sperm fine structure and relationships to phylogeny. In particular, the sperm structures of two primitive crustaceans, a cephalocarid, Hutchinsoniella macracantha, and a mystacocarid, Derocheilocaris typicus, were thoroughly examined. In addition, a brief comparison was made with the sperm of the branchiopod, Artemia salina, also a primitive crustacean, but phylogenetically divergent from the above two species (Dahl, 1963; Sanders, 1963; Hessler, 1964). This comparison showed the Artemia sperm to be quite unique morphologically. Therefore, a more thorough study of the development and function of this cell was undertaken