Odontaspis winkleri 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 : 52-53

Odontaspis winkleri Leriche, 1905

Fig. 18

Odontaspis winkleri sp. nov. Leriche, 1905: 74, pl. 6, fig. 8.

Odontaspis (Odontaspis) aff. winkleri – Arambourg 1935: 425 , pl. 29, figs 20–22.

Synodontaspis? winkleri – Herman 1977: 245 .

Eugomphodus winkleri – Krukow & Thies 1990: 35 .

Material examined

UNITED STATES OF AMERICA – Alabama • 5 isolated teeth; Claiborne Group; SC 2012.47.92, MSC 33380, MSC 35764, MSC 38477, WSU CC 535.1.

Description

Teeth small, generally not exceeding 1.0 cm in overall height. Upper teeth slightly sigmoidal; lower teeth with slight lingual bend. Teeth with tall and thin cusp, with characteristically tall, erect, conical and sharply pointed lateral cusplets. Lingual face of main cusp strongly convex; labial face may be nearly flat to convex (particularly at the base). Mesial and distal cutting edges absent or restricted to the upper two-thirds of the main cusp. Lingual and labial cusp faces of anterior teeth smooth, but lateral teeth with distinct folding at labial crown foot. Anterior teeth with single pair of lateral cusplets; lateral teeth with two to three pairs of lateral cusplets. Cusplets divergent and decrease in size laterally. Root bilobate with long, thin, divergent, and rounded lobes; lobes separated by deep U-shaped interlobe area. Deep nutritive groove located on prominent lingual root protuberance.

Remarks

Three species of Paleogene Odontaspis have been recognized in North America including O. carolinensis Case & Borodin, 2000 , O. speyeri Dartevelle & Casier, 1943 , and O. winkleri Leriche, 1905 . The Odontaspis teeth in our sample differ from those of O. carolinensis by having a less robust main cusp on the anterior teeth and cylindrical, not labiolingually flattened, lateral cusplets on the lateral teeth. The teeth of O. speyeri are much more robust and have smaller cusplets than those in our sample, and Cappetta (2012) referred this species to Jaekelotodus . Although Holman & Case (1988) reported O. speyeri from the ACov-11 locality, this was likely a misidentification as no such teeth have been identified within our exceptionally large sample of teeth from this locality, nor have they been reported by Clayton et al. (2013) or Cappetta & Case (2016). Furthermore, O. speyeri is a taxon that has generally been reported from Paleocene deposits elsewhere (see Siverson 1995; Yarkov & Popov 1998; Adolfssen & Ward 2015). Unfortunately, Holman & Case (1988) did not figure their specimens so the identity of these teeth remains unconfirmed.

The teeth in our sample appear to be conspecific with Odontaspis winkleri as originally described by Leriche (1905). These teeth are differentiated from other odontaspids in our sample by their tall, cylindrical lateral cusplets, reduced or absent cutting edges on anterior teeth, and presence of distinctive folds at the base of the labial cusp face on lateral teeth.

Stratigraphic and geographic range in Alabama

The specimens in our sample were collected from the lower Tallahatta Formation at site ADl-1 and the basal Lisbon Formation at site ACov-11. Upper Ypresian to middle Lutetian, zones NP14 and NP15.

Figures

Fig. 18. Odontaspis winkleri Leriche, 1905, teeth. A–C. MSC 33380, anterior tooth, lower Tallahatta Formation. A. Labial view. B. Lingual view. C. Mesial view. D–F. SC2012.47.162, anterior tooth, basal Lisbon Formation. D. Labial view. E. Lingual view. F. Mesial view. G–I. MSC 35764, lateral tooth, lower Tallahatta Formation. G. Labial view. H. Lingual view. I. Mesial view. J–L. WSU CC535.1, lateral tooth, basal Lisbon Formation. J. Labial view. K. Lingual view. L. Mesial view. Scale bars = 5 mm.