. Bulletin of the British Museum (Natural History), Geology. CASSIOPIDAE 249 According to d'Orbigny, the type species occurs at four localities in southern France: Uchaux (type locality) and Mondragon (Vauclause); La Cadiere and Sainte-Baume (Var): exposures at these localities range from Turonian to lower Campanian in age. However, later authors have recognized some of these specimens as belonging to other species, gibbosa (Repelin) and caderensis (Repelin); see Mennessier (1984: 68-71). The genus ranges from the Albian to the Cenomanian and the inclusion of G. pizcuetana (Vilanova) woul
. Bulletin of the British Museum (Natural History), Geology. CASSIOPIDAE 249 According to d'Orbigny, the type species occurs at four localities in southern France: Uchaux (type locality) and Mondragon (Vauclause); La Cadiere and Sainte-Baume (Var): exposures at these localities range from Turonian to lower Campanian in age. However, later authors have recognized some of these specimens as belonging to other species, gibbosa (Repelin) and caderensis (Repelin); see Mennessier (1984: 68-71). The genus ranges from the Albian to the Cenomanian and the inclusion of G. pizcuetana (Vilanova) would extend this back into the Aptian. If one followed Mennessier (1984: 66-74) the range would be Berriasian to Campanian, but we doubt whether all the species he hsts should be included; relevant literature also indicates that the ages of several are wrongly ascribed. Yet, the very small shells from the Upper Valanginian-Barremian found in the Prov- ince of Rioja, Spain, and described as Paraglauconia (Diglauconia) vierai by Mennessier & Calzada (1985: 139, 142; figs 1, 3, 4), would appear to have some affinity with Gymnentome and indicate its earlier occurrence. These relatively smooth cassiopids have growth lines and shells that are closely comparable to those of other later species of Gymnentome; they would seem to be misplaced in P. (Diglauconia) as their ornament does not conform to the diagnosis of that subgenus! It is possible that G. pizcuetana represents the stock from which many European species have evolved and this could account for its dissimilarity from the commoner, less ornamented, later forms that are readily recognized as Gymnentome. Gymnentome pizcuetana (Vilanova, 1859) Figs. 7, 8 1859 Pleurotomaria pizcuetana Vilanowa: p\. 2, fig. 12. 1865 Cassiope pizcuetana (Vilanova) Coquand: 248; pi. 3, figs 1, 2. 1865 ? Cassiope zekellii Coquand: 248-9; pi. 3, fig. Fig. 7 Gymnentome pizcuetana (Vilanova, 1859). 1, BMNH , H. S. Beckles colln; Crackers, Athe
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