. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . ANTHOCERATINA Hyatt, 1900 (nom. transl. Cooper 1991 ex Acanthoceratida Hyatt, 1900) Superfamily ACANTHOCERATACEAE de Grossouvre, 1894 Family Vascoceratidae Douville, 1912 Genus Vascoceras Choffat, 1898 Type species Vascoceras gamai Choffat, 1898; by the subsequent designation of Diener, 1925: 182. Vascoceras cf. proprium (Reyment, 1954)Fig. 17 Compare: 1954 Pachyvascocerasproprium Reyment, p. 258, pi. 5 (fig. 1), fig. Subtissotial sp.; Cooper, p. 248. 1987 Vascoceras proprium (Reyment); Kennedy et al, p. 46,
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . ANTHOCERATINA Hyatt, 1900 (nom. transl. Cooper 1991 ex Acanthoceratida Hyatt, 1900) Superfamily ACANTHOCERATACEAE de Grossouvre, 1894 Family Vascoceratidae Douville, 1912 Genus Vascoceras Choffat, 1898 Type species Vascoceras gamai Choffat, 1898; by the subsequent designation of Diener, 1925: 182. Vascoceras cf. proprium (Reyment, 1954)Fig. 17 Compare: 1954 Pachyvascocerasproprium Reyment, p. 258, pi. 5 (fig. 1), fig. Subtissotial sp.; Cooper, p. 248. 1987 Vascoceras proprium (Reyment); Kennedy et al, p. 46, pi. 4 (figs 1-15, 18-19), pis 5-6, figs 8A-C, 9 (cum synon.). Material A single specimen, SAM-PCA1891 from Bed II, partially eroded but preservingrecrystallized test. Description The shell is strongly inflated, globose, with a very narrow, crater-like umbilicus (about15% of the diameter). The overhanging umbilical wall is broad, convex, with a wellrounded shoulder. The convex flanks converge rather rapidly to the evenly rounded venter 122 ANNALS OF THE SOUTH AFRICAN MUSEUM. Figure 18 Morrowites mocamedensis (Howarth). X 1. A. Lateral view of SAM-PCA1892. B. Lateral view ofSAM-PCA1887. C-D. Lateral and ventral views of SAM-PCA1889. UPPER CRETA CEOUS (TVRON IAN-CON I A CIAN) AMMONITES FROM SA O NICOLA U, ANGOLA 123 to produce a subtrigonal whorl section. Ornament is lacking and the suture is notdisplayed. Slight deformation and erosion make morphometric analysis unreliable andmeasurements are excluded. Discussion Although poorly preserved, the Angolan example shows all the essential features ofReyments (1954) species. Given the wide range of variation admitted for V. proprium ( et al. 1987), it may prove to be a subjective junior synonym of (Pervinquiere). Vascoceras hartti (Hyatt) (1870: 386; 1903: 103, pi. 14 (fig. 16); White 1887: 226,pi. 19 (figs 1-2), pi. 20 (fig. 3); Chancellor 1982: 98, figs 28C, 29-33) resembles thepresent specimen, especially
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Keywords: ., bookcentury1800, bookdecade1890, booki, booksubjectnaturalhistory
