Sciaenidae gen. et sp. indet.

Figs 26T–W, 27

Material examined

UNITED STATES OF AMERICA – Mississippi • 5761 isolated teeth; Catahoula Formation; SC 2013.28.809 (Fig. 27F–H), SC 2013.28.810, SC 2013.28.811 (Fig. 27I–K), SC 2013.28.812, SC 2013.28.813 (79 teeth), SC 2013.28.842 (5678 teeth) • 16 pharyngeals; Catahoula Formation; SC 2013.28.684 (Fig. 27C–E), SC 2013.28.685 to 28.689, SC 2013.28.690 (9 specimens), SC 2013.28.691 • 192 sagittae; Catahoula Formation; MMNS VP-7457 (2 specimens), MMNS VP-7460.2, MMNS VP-8712.3 (Fig. 26T–U), MMNS VP-8712.4 (Fig. 26V–W), MMNS VP-8933 (2 specimens), MMNS VP-8933.1 (Fig. 27A–B), SC 2013.28.759, SC 2013.28.773, SC 2013.28.777, SC 2013.28.780, SC 2013.28.784, SC 2013.28.785, SC 2013.28.787, SC 2013.28.790, SC 2013.28.792, SC 2013.28.798 to 28.800, SC 2013.28.806 (6 specimens), SC 2013.28.807 (12 specimens), GLS otolith comparative collection (154 specimens) .

Description

The best-preserved sciaenid jaw element is an edentulous lower right pharyngeal (Fig. 27C–E). In aboral and oral views, the bone has a somewhat triangular outline. The symphyseal margin is rather straight and would have abutted (but not fused) with the left pharyngeal. The labial margin is relatively straight and intersects the symphyseal margin at a blunt anterior point. Posteriorly the labial margin extends away from the symphysis, and the distal margin is convex. The oral surface bears alveoli and broken tooth bases that are loosely arranged into rows that parallel the labial margin. The teeth are largest anteriorly, but teeth located at the distal one-third of the jaw were only about one-half as large. In symphyseal view, the symphyseal surface is high, especially medially, and the anterior end of the bone curves dorsally. The ventral strut that buttressed the bone against the cleithrum is incompletely preserved.

Isolated teeth consist of a moderately high crown and base that comprises one-third or less of the total tooth height (Fig. 27F–K). The crown is covered by a relatively thin layer of smooth enameloid that ends abruptly at the base (Fig. 27G, J). The occlusal surface of unworn teeth is weakly to moderately convex, but the crowns of worn teeth exhibit a flat surface with exposed dentine. The occlusal outline is polygonal (i.e., four-sided to six-sided; Fig. 27F, I), and the sides of the crown are flat and vertical. In basal view, a small and deep pulp cavity is framed by a thick wall of dentine (Fig. 27H, K).

Remarks

Herein included within undetermined sciaenid fishes are isolated teeth, pharyngeal tooth plates, and poorly preserved otoliths. The pharyngeal bones are largely abraded and incomplete, often hindering our ability to determine their location in the jaw let alone the taxon represented. The isolated teeth are reminiscent of several sciaenid species, and we could not conclusively determine that they are representative of any one of the taxa we identified by otoliths. The otoliths are not well enough preserved for us to assign them to a particular genus (i.e., Fig. 26T), and it is unclear whether they represent one of the taxa described herein. All of these specimens are included here for completeness.