Some aspects of the anatomy of Ochetostoma caudex (Echiura) from the east coast of southern Africa with Remarks on its taxonomic status

Abstract

The degree of variation within the species Ochetostoma caudex was determined from 32 specimens collected from the east coast of southern Africa. The shape and distribution of the dermal papillae were uniform in all the specimens. The number of longitudinal muscle bands ranged from 14 to 21 with 16 to 19 being the most common. In most specimens the anal vesicles were almost equal to or slightly longer than the trunk and were covered with numerous, unstalked ciliated funnels. A comparison of O. caudex with related species (O. australiense, O. palense, O. indosinense and O. erythrogrammon) revealed differences which justify the retention of O. caudex as a distinct species. Hence the contention by some authors that O. caudex and O. erythrogrammon are synonymous, appears unjustified. O. griffinl and O. multilineatum may prove to be conspecific with O. caudex. O. kokotoniense and O. stuhlmanni are too poorly known for a detailed comparison