This very distinctive monospecific taxon was described in superb detail by Loven (1883), and the type refigured by Kier (1977). The large size of the apical disc and basicoronal plate suggests that this might still be a juvenile, although gonopores are open. It is impossible to confuse with any other echinoid because of its small number of interambulacral plates and their distinctive arrangement.
Loven, S. 1883. On Pourtalesia, a genus of Echinoidea. Kongliel Svenska Vetenskaps-Akademiens Handlingar new series 19, 1-95, pls 1-21.
Kier, P. M. 1977. Triassic echinoids. Smithsonian Contributions to Paleobiology 30, 1-88.