. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. B Fig. 16. 'Allocrioceras' sp., SAM-Z2071 from locality 105, Zululand, St Lucia Formation, uppermost Santonian or basal Campanian. Note the distinct bituberculate flared ribs, x 1. of an initial straight shaft, followed by a helical whorl and a series of closely connected U-shaped sections, ending in a retroversal body chamber hook. Orna- ment as in Hyphantoceras with major quadrituberculate ribs and intermediary, fine, non-tuberculate ribs. The genus is thus far only known from the Upper Turonian of
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. B Fig. 16. 'Allocrioceras' sp., SAM-Z2071 from locality 105, Zululand, St Lucia Formation, uppermost Santonian or basal Campanian. Note the distinct bituberculate flared ribs, x 1. of an initial straight shaft, followed by a helical whorl and a series of closely connected U-shaped sections, ending in a retroversal body chamber hook. Orna- ment as in Hyphantoceras with major quadrituberculate ribs and intermediary, fine, non-tuberculate ribs. The genus is thus far only known from the Upper Turonian of Hokkaido. It differs from Nipponites by the Hyphantoceras-\ik& ornament, and from the latter genus by its distinctive coiling. 5. Klinger (1976: 71, pi. 32 (fig. 5a-b), pi. 33 (figs 2-3), text-fig. lOd-e) identified Van Hoepen's (1921: 17, pi. 4 (figs 1-2)) Heteroceras amapondense from the uppermost Santonian and basal Campanian of Pondoland and Zululand as Hyphantoceras (Madagascarites?) amapondense. The lower Campanian Madagascan species described as Anaklinoceras? stephensoni by Collignon (1969: 50, pi. 532 (fig. 2096)) was regarded as a synonym of the former. Klinger's reasons for this identification were that the ascending body chamber of H. amapondense was reminiscent of that of Madagascarites, whereas the orna- mentation of the late growth stage with periodic flared ribs, was reminiscent of Hyphantoceras. This tentative generic and subgeneric designation was followed by Summesberger (1979, 1980), Lewy (1983), Klinger (1985), Immel (1987), Kennedy & Cobban (1991) and Wright (1996). Comparison with the type species of Hyphantoceras and Madagascarites shows that Heteroceras amapondense belongs to neither genus. It lacks the quadrituberculate ornament of both; instead, it has Hamites- or Eubostrychoceras-likQ ornament on the early whorls, with periodic flared ribs appearing at later growth stages. Klinger (1976: 72) stated that well-preserved H. amapondense had flar
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