Scomberomorus stormsi ( Leriche, 1905 )

Ebersole, Jun A., Cicimurri, David J. & Stringer, Gary L., 2019, Taxonomy and biostratigraphy of the elasmobranchs and bony fishes (Chondrichthyes and Osteichthyes) of the lower-to-middle Eocene (Ypresian to Bartonian) Claiborne Group in Alabama, USA, including an analysis of otoliths, European Journal of Taxonomy 585, pp. 1-274 : 176

Scomberomorus stormsi ( Leriche, 1905)

Fig. 64 S–AA

Cybium stormsi Leriche, 1905: 151 , pl. 10, fig. 3.

Scomberomorus stormsi – Bannikov 1982: 135 .

Material examined

UNITED STATES OF AMERICA – Alabama • 12 isolated teeth; Claiborne Group ; MSC 37126, MSC 37512.1 – 2 , MSC 38974.1 – 3 , MSC 38977, SC 2012.47.248 (5 specimens) .

Description

Teeth measuring up to 1.0 cm high, 5.0 mm wide. Crown medially curved, biconvex; medial face more convex than lateral face; faces with thin layer of enameloid; enameloid smooth or finely striated basally. Crown bicarinate; carinae smooth, sharp, not reaching the tooth base; basal half of carinae straight, nearly parallel; tapering to point apically. Basal part of tooth more cylindrical, appears constricted below end of carinae. Tooth base with ovate outline, weak pulp cavity.

Remarks

Scomberomorus stormsi ( Leriche, 1905) and S. bleekeri ( Storms, 1892) are coeval within Eocene strata ( Casier 1946, 1966; Weems 1999), but the former can be differentiated from the latter by being more ovate in basal view and being twice as high as wide. The teeth of S. stormsi can also exhibit longitudinal striations on the labial and lingual faces. This species can be differentiated from teeth of Palaeocybium proosti and Sphyraena sp. in having carinae that do not reach the tooth base, a much smaller pulp cavity than P. proosti , and a labiolingually thicker crown than Sphyraena sp.

Stratigraphic and geographic range in Alabama

The specimens in our sample were collected from the lower Tallahatta Formation at site ADl-1, the contact of the Tallahatta and Lisbon formations and the basal Lisbon Formation at site ACov-11, and the basal Gosport Sand at site ACl-15. Upper Ypresian to middle Bartonian, zones NP14 to NP17.

Figures

Fig. 64. Palaeocybium proosti (Storms, 1897) and Scomberomorus Lacépède, 1802, teeth. A–I. Palaeocybium proosti A–C. MSC 37194.4, Tallahatta/Lisbon formation contact zone, courtesy of T. Prescott Atkinson. A. Lingual view. B. Carinal view. C. Basal view. D–F. MSC 37423, basal Gosport Sand. D. Lingual view. E. Carinal view. F. Basal view. G–I. MSC 38500.2, basal Gosport Sand. G. Lingual view. H. Carinal view. I. Basal view. — J–R. Scomberomorus bleekeri (Storms, 1892). J–L. MSC 37147, Tallahatta/Lisbon formation contact zone, courtesy of James Lowery. J. Lingual view. K. Carinal view. L. Basal view. M–O. MSC 35777.2, basal Gosport Sand. M. Lingual view. N. Carinal view. O. Basal view. P–R. MSC 37268.1, basal Lisbon Formation. P. Lingual view. Q. Carinal view. R. Basal view. — S–AA. Scomberomorus stormsi (Leriche, 1905). S–U. MSC 37512.1, basal Gosport Sand. S. Lingual view. T. Carinal view. U. Basal view. V–X. MSC 37126, Tallahatta/Lisbon formation contact zone, courtesy of James Lowery. V. Lingual view. W. Carinal view. X. Basal view. Y–AA. MSC 38974.1, lower Tallahatta Formation. Y. Lingual view. Z. Carinal view. AA. Basal view. Scale bars = 2 mm.