basis of recordClark, A. M. (1974). Notes on some echinoderms from southern Africa. <em>Bulletin of the British Museum of Natural History (Zoology).</em> 26(6): 423-487, 3 pls, 16 figs, 1 map, 3 tables., available online athttps://www.biodiversitylibrary.org/page/2294231[details]