Hemipristis, AGASSIZ, 1835

Cicimurri, David J., Knight, James L. & Ebersole, Jun A., 2022, Early Oligocene (Rupelian) fishes (Chondrichthyes, Osteichthyes) from the Ashley Formation (Cooper Group) of South Carolina, USA, PaleoBios 39 (1), pp. 1-38 : 8

HEMIPRISTIS CF. H. SERRA AGASSIZ, 1835

FIG. 5A

Type species — Hemipristis serra Agassiz, 1835 ; Miocene , Germany .

1999 Hemipristis serra Agassiz ; Müller, p. 54, plate 8, fig. 9.

2009 a Hemipristis serra Agassiz ; Cicimurri and Knight; p. 634, fig. 5I.

Referred specimens (n=6) —SC2007.36.7 ( Fig. 5A ), SC2007.36.8, SC2007.36.9 (four teeth).

Remarks — Cicimurri and Knight (2009a) reported Hemipristis serra from the Chattian Chandler Bridge Formation, and the taxon has been reported from the Oligocene Old Church Formation of Virginia ( Müller 1999). Interestingly, although Hemipristis has been documented from Oligocene strata of Pakistan ( Adnet et al. 2007) and Oman ( Thomas et al. 1989), it is not known from the European Oligocene. Müller (1999:54) commented that H. serra was common in warm waters during the Neogene, and von der Hocht (1978b) hypothesized that the absence of Hemipristis in the European Rupelian is related to the colder water conditions that existed during that time.

Adnet et al. (2007) and Ebersole et al. (2021) considered the possibility that their Oligocene Hemipristis teeth represented a transitional species from H. curvatus Dames, 1883 (Eocene) to H. serra (Oligocene to Early Pleistocene), and Chandler et al. (2006) reported Comparison of the Ashley Formation teeth to a limited sample from the Chandler Bridge Formation (SC2005.2) revealed close similarities in both tooth size and number of mesial/distal serrations, and the material appears to be conspecific. The H. serra teeth from the Miocene Pungo River Formation of North Carolina (SC98.46) are much larger than the South Carolina Oligocene teeth, and for this reason we only tentatively identify the Ashley Formation specimens to H. serra .

Figures

Figure 5. Selachian teeth from the Givhans Ferry Member, Ashley Formation (Rupelian), Dorchester County, South Carolina. A. Hemipristis cf. H. serra tooth, SC2007.36.7 in labial view. B. Carcharhinus gibbesi upper tooth, SC2007.36.14 in labial view. C. Carcharhinus gibbesi lower tooth, SC2007.36.15 in labial view. D. Physogaleus cf. P. contortus tooth, SC2007.36.19 in labial view. E. Physogaleus sp. tooth, SC2007.36.21 in labial view. F. Galeocerdo aduncus tooth, SC2007.36.17 in labial view. G. Sphyrnidae Morphotype 1 tooth, SC2007.36.26 in labial view. H. Sphyrnidae Morphotype 2 tooth, SC2007.36.24 in labial view. Scale bar=3 mm in E; 5 mm in A, C, D, F, G; 10 mm in B.