Rhynchoconger, Jordan & Hubbs, 1925

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 : 192

Rhynchoconger sp.

Fig. 69 M–N

Hildebrandia sp. – Stringer 1992: 36, fig. 2a. — Müller 1999: 80, pl. 20, figs 28–30.

Rhynchoconger sp. – Nolf & Stringer 2003: 4, pl. 1, figs 12a–b.

Material examined

UNITED STATES OF AMERICA – Alabama • 1 otolith; MSC 37059.6 .

Description

Sagitta with elliptical outline; somewhat elongate with a height/length ratio of 48%. Shape noticeably angular, with greatest height slightly anterior to mid-point on dorsal margin. Margins smooth. Anterior tapered but with rounded shape. Posterior also tapered but more pointed. Inner face slightly convex, with distinct undivided sulcus. Sulcus slants slightly in posteroventral direction, covers approximately 60% of inner face. Width of sulcus fairly consistent. Small ostial channel connects ostial portion of sulcus to anterodorsal margin. Ostial channel situated away from anterior margin of sulcus. Well-defined rectangular depressed area above sulcus. No indication of ventral furrow. Outer face slightly convex.

Remarks

Only one specimen, an ablated juvenile sagitta, was attributed to Rhynchoconger . However, features of the sulcus and the presence of a depressed area above the cauda are indicative of Rhynchoconger . Unfortunately, specific determination was not possible.

Stratigraphic and geographic range in Alabama

The one specimen of Rhynchoconger sp. was recovered from the “upper” Lisbon Formation at site ACh- 7. Bartonian, zones NP16 and NP17.

Figures

Fig. 69. Claiborne Group, “upper” Lisbon Formation, otoliths. A–B. Albula sp., MSC 562. A. Inner face (right sagitta). B. Dorsal view. — C–D. Pythonicthys colei (Müller, 1999), WSU CC 474. C. Inner face (left sagitta). D. Dorsal view. — E–F. Muraenesocidae Kaup, 1859, indet., MSC 39064. E. Inner face (left sagitta). F. Dorsal view. — G–H. Ariosoma nonsector Nolf & Stringer, 2003, MSC 39069. G. Inner face (left sagitta). H. Dorsal view. — I–J. Paraconger sector (Koken, 1888), MSC 39052. I. Inner face (right sagitta, broken on anterodorsal angle). J. Dorsal view. — K–L. Pseudophichthys sp., MSC 37059.2. K. Inner face (right sagitta). L. Dorsal view. — M–N. Rhynchoconger sp., MSC 37059.6. M. Inner face (left sagitta). N. Dorsal view. — O–P. Gnathophis meridies (Frizzell & Lamber, 1962), MSC 37059.XX. O. Inner face (right sagitta). P. Dorsal view. — Q–R. Myripristis sp., MSC 39047. Q. Inner face (right sagitta). R. Dorsal view. Scale bars: A–B =5 mm; C–R =2 mm.