Late Eocene (Priabonian) elasmobranchs from the Dry Branch Formation (Barnwell Group) of Aiken County, South Carolina, USA Author Cicimurri, David J. Author Knight, James L. text PaleoBios 2022 36 1 31 journal article 10.5070/P9361043964 0031-0298 13750243 3F95876E-933FF-48AF-9CF0-A840A333220B RHIZOPRIONODON ? GANNTOURENSIS ( ARAMBOURG, 1952 ) ( FIG. 3J–L ) Referred specimens —SC96.97.2, four teeth; SC 2001.1.18 , tooth; SC 2001.1.19 , 40 teeth;SC2013.38.98, anterior tooth ( Fig. 3J, K );SC2013.38.99, lateral tooth ( Fig. 3L ); SC2013.38.100, 18 teeth; SC2013.38.101, 32 teeth; SC2013.38.102, eight posterior teeth; SC2013.38.103, eight distal lateral teeth. Remarks —One hundred thirteen Dry Branch Formation teeth are similar to those of extant Rhizoprionodon , and to Eocene Rhiz. ganntourensis, in particular. The distal heel of Rhizoprionodon , including Rhiz. ganntourensis , is generally cuspidate ( Arambourg 1952 , Herman et al. 1991 , Case et al. 1996 , Noubhani and Cappetta 1997, Mustafa et al. 2005), but our specimens lack enameloid and this feature is not preserved. However, we examined a tooth of Rhiz . sp. cf. Rhiz. ganntourensis that was recovered by Zullo and Kite (1985) from the Griffins Landing Sand (see Appendix 1), and found that it is very similar to the material listed above. The well preserved Griffins Landing Sand tooth exhibits a cuspidate distal heel, but the translucent enameloid allows us to view the unifromly convex dentine core of the heel, as can be seen on the specimens in our sample.