Diplodus undetermined

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 : 27

DIPLODUS SP.

FIG. 11Z –CC

Type species — Sparus annularis, Linnaeus 1758 ; Recent.

Referred specimens (n=16) —SC2015.29.195 (13 teeth), SC2015.29.222 ( Fig. 11Z , AA), SC2015.29.223, SC2015.29.224 ( Fig. 11 BB, CC).

Description —Tooth crowns are mesio-distally wide (less than 5 mm) but very thin labio-lingually. The labial face is weakly convex across crown width, whereas the lingual face is weakly concave. Both faces are covered by a thick layer of smooth enameloid. The occlusal surface of unworn specimens is thin and convex, but worn specimens exhibit a flat and straight occlusal surface. The crown is basally tapered, and enameloid ends where the tooth base begins. The tooth base has a deep and mesio-distally extended reniform-shaped pulp cavity.

Remarks —These labio-lingually compressed crowns are similar to the incisiform teeth identified as Diplodus sp. from the Miocene of Costa Rica ( Laurito Mora 1999) and as Sargus (= Diplodus ) laticonus Davis, 1888 from the New Zealand Neogene (also Chapman 1918). We have not conducted an exhaustive review of Sparidae incisiform teeth, but the specimens described herein differ from those of Archosargus sp. (see above) by being very antero-posteriorly compressed, with weakly convex labial face and weakly concave lingual face and lacking a well-defined lingual protuberance.

Figures

Figure 11. Teleost teeth from the Givhans Ferry Member, Ashley Formation (Rupelian), Dorchester County, South Carolina. A, B.?Sciaenops sp. tooth, SC2007.36.200.1 in profile (A) and basal (B) views. C, D.?Sciaenops sp. tooth, SC2007.36.200.2 in profile (C) and basal (D) views. E–G.?Pogonias sp. tooth, SC2007.36.196 in occlusal (E), profile (F), and basal (G) views. H–J.?Calamus sp. tooth, SC2007.36.198 in occlusal (H), profile (I), and basal (J) views. K–M. Archosargus sp. molariform tooth, SC2007.36.197 in occlusal (K), profile (L), and basal (M) views. N–Q. Archosargus sp. incisiform tooth, SC2007.36.200 in profile (N), lingual (O), labial (P), and basal (Q) views. R–U. Archosargus sp. incisiform tooth, SC2015.29.219 in profile (R), lingual (S), labial (T), and basal (U) views. V, W. Archosargus sp. pharyngeal tooth, SC2007.36.192 in profile (V) and anterior (W) views. X, Y. Archosargus sp. pharyngeal tooth, SC2007.36.193 in profile (X) and anterior (Y) views. Z, AA. Diplodus sp. tooth, SC2015.29.222 in lingual (Z) and posterior (AA) views. BB‒CC. Diplodus sp. tooth, SC2015.29.224 in lingual (BB) and posterior (CC) views. Scale bar=0.5 mm in V,W; 1 mm in A–U, X–CC.