Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . Paratexanites species already occur in western andcentral Europe, North Africa, the Gulf Coast region of North America, Hok-kaido, and Zululand by Late Coniacian time. Wiedmann (1960), however,reports Protexanites bourgeoisie Protexanites cf. bontanti, and Protexanitessp. nov. from the Lower Coniacian of the Vascogotic region of the IberianPeninsula, which may substantiate Collignons views. The rate of dispersionthus seems to have been very rapid. During Santonian time, four main regions of development were alreadyest
Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . Paratexanites species already occur in western andcentral Europe, North Africa, the Gulf Coast region of North America, Hok-kaido, and Zululand by Late Coniacian time. Wiedmann (1960), however,reports Protexanites bourgeoisie Protexanites cf. bontanti, and Protexanitessp. nov. from the Lower Coniacian of the Vascogotic region of the IberianPeninsula, which may substantiate Collignons views. The rate of dispersionthus seems to have been very rapid. During Santonian time, four main regions of development were alreadyestablished: western and central Europe and the Middle East; the Gulf Coastand adjacent areas of North America; Hokkaido and environs; and Mada-gascar and South Africa; with minor centres in north Africa (Algeria), westAfrica (Nigeria and Cameroons), south-western Africa (Angola), and northernSouth America (Venezuela and Peru). In terms of numbers and diversity, thecentre of maximum development appears to be Madagascar and South Africa. 352 ANNALS OF THE SOUTH AFRICAN MUSEUM. O PLESIOTEXANITES• REGINAITESA TEXANtTESD DEFORDICERAS? BEVAHHES© SUBMORTONICERAS^^^ MENABITES^ 3 RARATEXANITES - Fig. 268. Palaeobiogeography of Texanitinae during Middle to Late Santonian time.(Map after Smith et al, 1973, fig. 7.) Even though the majority of species in Santonian time appear to be endemicto these four main regions, faunal exchange did take place on a Umited scale,as shown by the distribution of Plesiotexanites stangeri (Madagascar, SouthAfrica, Hokkaido, and Gulf Coast). During Early and Middle Campanian times, endemism and developmentof the Texanitinae seems to have reached its peak. Again Madagascar andSouth Africa seem to have been the centre of development as exemplified bythe large number of Menahites and Submortoniceras species, even if excessivetaxonomic splitting is taken into account. In Europe, texanitine species decreasednumerically, and this region was now of subordinate
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