Special Publication (J.L.B. Smith Institute of Ichthyology) no.22

Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 22Plotosus nkunga sp. n., from the east coast of South Africa, possibly ranging as far north as Zanzibar, is most similar to Plotosus limbatus Valenciennes, from the coasts of India, Sri Lanka, Kenya and Aldabra. Plotosus nkunga differs most notably in having fewer total gill rakers on the anterior faces of the first two arches, 16 to 21 versus 20 to 25 first arch, 16 to 24 versus 23 to 27 second arch; in having modally one more precaudal vertebra and slight modal differences in number of ribs and branchiostegal rays; in the shapes of the mesethmoid and the parapophyses of the fourth and fifth centra of the anterior complex vertebra; in the length of the maxilla; and in certain body proportions. Descriptions, annotated synonymies and illustrations are given for both species. A key to the five known species of Plotosus is presented