. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. 78 ANNALS OF THE SOUTH AFRICAN MUSEUM L. NEOCOMIAN HAUTERIVIAN BARREMIAN. Fig. 3. Suggested phylogeny of major branches of Crioceratites to illustrate trend towards recoiling according to Thieuloy (1964). 1. Protancyloceras kurdistanense. 2. Himantoceras tri- nodosum. 3. Crioceratites (C.) nolani. 4. C. (C.) duvali. 5. C. (C.) villersianus. 6. C. (C.) majoricensis. 7. C. (Pseudothurmannia) angulicostata. 8. C. (Emericiceras) emerici. (Redrawn after Thieuloy 1964, text-fig. 3.) As far as the strong tr
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. 78 ANNALS OF THE SOUTH AFRICAN MUSEUM L. NEOCOMIAN HAUTERIVIAN BARREMIAN. Fig. 3. Suggested phylogeny of major branches of Crioceratites to illustrate trend towards recoiling according to Thieuloy (1964). 1. Protancyloceras kurdistanense. 2. Himantoceras tri- nodosum. 3. Crioceratites (C.) nolani. 4. C. (C.) duvali. 5. C. (C.) villersianus. 6. C. (C.) majoricensis. 7. C. (Pseudothurmannia) angulicostata. 8. C. (Emericiceras) emerici. (Redrawn after Thieuloy 1964, text-fig. 3.) As far as the strong trituberculation of the major ribs and the low number of intermediaries on the inner whorls are concerned, 'Cryptocrioceras' finds its closest match in the group of Crioceratites (C.) barremense (Kilian, 1895). Species referable to this group include C. (C.) barremense (Kilian, 1895: 978; see also Simionescu 1900: 14, pi. 1 (figs 4-5)), C. (C.) thomeli Immel, 1978 (= Crioceratites (Emericiceras) collignoni Thomel, 1964: 33, pi. 6 (fig. 4), text- fig. 3), C. (C.) alpinus (d'Orbigny, 1850: 100; see also Cottreau 1937: 63, pi. 78 (figs 16-17)), and C. (C.) janus Thieuloy, 1979: 310, pi. 2 (figs 1-4)). The Upper Barremian occurrence of this species group also matches that of 'Crypto- crioceras\ Unfortunately, very little is known of the overall (adult) shell of these species. From the available figures, however, it does seem that at least C. (C.) alpinus, C. (C.) thomeli and, to a lesser extent, C. (C.) barremense have open, crioceratitid coiling, quite unlike that of lCryptocrioceras\ Crioceratites (C.) janus has the closest coiling of the group and shows the distinct change from major trituberculate ribbing on the phragmocone to simple ribbing on the body chamber. All the specimens of C. (C.) janus figured by Thieuloy (1979) are small in comparison to the other species in this group, and we are not sure if these are all juveniles or possibly micromorphs. In the group of C. (C.) que
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