Sparidae gen. et sp. indet.

Fig. 29C–J

Material examined

UNITED STATES OF AMERICA – Mississippi • 1041 isolated teeth; Catahoula Formation; SC 2013.28.664 to 28.666, SC 2013.28.667 (6 specimens), SC 2013.28.668 (Fig. 29I–J), SC 2013.28.669, SC 2013.28.670 (3 specimens), SC 2013.28.671 (3 specimens), SC 2013.28.672, SC 2013.28.673 (4 specimens), SC 2013.28.674 (4 specimens), SC 2013.28.675, SC 2013.28.676 (4 specimens), SC 2013.28.903 (Fig. 29C–E), SC 2013.28.904 (Fig. 29F–H), SC 2013.28.907, SC 2013.28.910 (1007 specimens) .

Description

In addition to Diplodus sp., at least two other sparid tooth morphotypes occur in the Catahoula Formation. One morphotype, shown in Fig. 29C–H, is represented by low- and high-crowned specimens. Low-crowned specimens have a weakly to moderately convex occlusal surface (compare Fig. 29D to G) and circular to ovate occlusal outline (compare Fig. 29C to F). High-crowned specimens are cylindrical with a very convex occlusal surface and circular occlusal outline. Regardless of crown height, there is a conspicuous basal band that is distinguished by a weak cingulum (Fig. 29G). In basal view, a large pulp cavity is framed by a thick dentine wall with a thick external enameloid covering (Fig. 29E, H).

Another morphotype is like that shown in Fig. 29I–J. These teeth are also of variable height, but all have a very convex labial face and less convex lingual face. In profile view, the crown is medially curved and the labial and lingual faces are asymmetrically divided by blunt carinae that may or may not reach the crown base (Fig. 29I). In basal view, the tooth base has a circular to slightly oval outline, and the central pulp cavity varies in size but is framed by a wall of dentine covered with thick external enameloid (Fig. 29J).

Remarks

Teeth within the jaws of extant Sparidae that we examined can be differentiated into incisiform, lateral, and molariform types. Incisiform teeth are located along the anterior margin of tooth plates, whereas lateral teeth occur along the lateral margins (i.e., Fig. 29I). Molariform teeth occur on the main body of a pharyngeal tooth plate and form most of a triturating surface (i.e., Fig. 29C, F). The lateral teeth identified as Diplodus sp. (see above) are easily separated from those assigned to Sparidae indet. by their thinness and sinuous anterior and posterior margins.