Intra- and interspecific variation in the chitin content of some anostracans

Chitin was assayed in adults of nine anostracan species (Streptocephalus dichotomus, S. proboscideus, S. simplex, S. torvicornis, Thamnocephalus platyurus, Dendrocephalus brasiliensis, Chirocephalus diaphanus, Artemia salina and Branchipus schaefferi) using a highly specific enzymatic method. Cysts of A. salina, T. platyurus and larvae of A. salina and S. simplex were also analysed for their chitin content. The results demonstrated a weak interspecific variation in chitin content among the adults. On the whole, it ranged from 9 to 33 mg chitin (g dry mass)(-1). In most species, the chitin level was not significantly different between males and females. In contrast, chitin levels varied significantly between cysts, larvae and adults within species. Comparison of the chitin content of anostracans revealed a comparable or lower chitin level than other crustaceans.