Rhynchobatus pristinus (Probst, 1877)

Cicimurri, David J. & Knight, James L., 2009, Late Oligocene sharks and rays from the Chandler Bridge Formation, Dorchester County, South Carolina, USA, Acta Palaeontologica Polonica 54 (4), pp. 627-647 : 635

Rhynchobatus pristinus (Probst, 1877)

Fig. 6A .

Referred specimens.—BCGM 9084–9086, SC 2009.18.14.

Comments.—Teeth of Rhynchobatus Müller and Henle, 1837 can be distinguished from Rhinobatos Link, 1790 in that crown enameloid has a granular texture, and the elongated medial lingual uvula is not flanked by lateral uvulae. Ontogentetic heterodonty in our Rhynchobatus pristinus sample is evident in that the enameloid of tiny teeth (~ 0.5 mm) is smooth and lacks the granular ornamentation seen on adult teeth.

Stratigraphic and geographic range.— Oligocene (Chattian), USA (South Carolina); Miocene, Europe and USA (North Carolina, Virginia) .

Figures

Fig. 6. Batoids from Summerville, upper Chattian. A. Rhynchobatus pristinus (Probst, 1877), BCGM 9085, occlusal view. B, C. Myliobatinae gen. indet. B. BCGM 9117, lateral tooth, occlusal view. C. BCGM 9116, partial medial tooth, occlusal (C1) and lingual (C2) view. D. Paramobula fragilis (Cappetta, 1970), BCGM 9113, anterolateral tooth, occlusal (D1), labial (D2), and lateral (D3) view. E, F. Plinthicus stenodon Cope, 1869. E. BCGM 9120, partial anterior tooth, lateral (E1) and lingual (E2) view. F. BCGM 9121, lateral tooth, lateral (F1) and labial (F2) view. G. Rhinoptera cf. R. studeri (Agassiz, 1843), BCGM 9123, occlusal (G1) and lingual (G2) view. H. Gymnura sp., BCGM 9107, lateral (H1) and labial (H2) view.