Alopias, Rafinesque, 1810

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 : 630-631

Alopias cf. A. vulpinus (Bonnaterre, 1788)

Fig. 4A, B .

Referred specimens.—BCGM 9046–9048, SC 2009.18.3.

Comments.—Several species of Alopias Rafinesque, 1810 have been reported from Oligocene marine strata, including A. exigua (Probst, 1879) and A. latidens (Leriche, 1909) (i.e., Leriche 1910; Steurbaut and Herman 1978; Baut and Génault 1999). The validity of these species, which have been differentiated on the basis of crown stockiness and development of cutting edges (i.e., Leriche 1908; Cappetta 1970), has been questioned by Purdy et al. (2001), citing ambiguities in the morphological criteria used to identify teeth and noting a high degree of interspecific variation between individuals within extant species. Case (1980) and Pfeil (1981) reported teeth of A. superciliosus (Lowe, 1841) , and those specimens are similar to the A. exigua morphology in having rather gracile crowns. This is in contrast to our Chandler Bridge specimens, which have a wide crown as in the A. latidens morphology. We conclude that the Chandler Bridge teeth do not differ morphologically from specimens of A. cf. A. vulpinus illustrated by Purdy et al. (2001: 108, fig. 22a), and we follow their taxonomic assignment. Of three Oligocene species illustrated by Reinecke et al. (2005), A. latidens (pl. 24), A. exigua (pl. 25), and A. aff. A. vulpinus (pls. 21, 22), our sample more closely compares with the latter−most taxon.

Stratigraphic and geographic range.—Oligocene (Chattian), USA (South Carolina); Mio−Pliocene, USA (North Carolina), extant.

Figures

Fig. 4. Lamniform sharks from Summerville, upper Chattian. A, B. Alopias cf. A. vulpinus (Bonnaterre, 1788). A. BCGM 9047, anterior tooth, labial view. B. BCGM 9048, lateral tooth, labial view. C. Carcharias sp., BCGM 9054, labial view. D. Carcharias cuspidatus (Agassiz, 1843), BCGM 9052, lower lateral tooth, labial view. E. Carcharocles sp., BCGM 9055, labial view.