Jefitchia copelandi Frizzell & Dante, 1965

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 : 215-216

Jefitchia copelandi Frizzell & Dante, 1965

Fig. 71 Q–R

Jefitchia copelandi Frizzell & Dante, 1965: 705 , pl. 87, figs 3–4, 9, pl. 88, figs 1–2, 6.

“genus Sciaenidarum ” aff. copelandi – Müller 1999: 161 , pl. 33, fig. 22.

“ Sciaenida ” copelandi – Nolf 2013: 107 , pl. 281.

Material examined

UNITED STATES OF AMERICA – Alabama • 21 otoliths; MSC 7299.1 , MSC 7299.2 , MSC 7299.3 , MSC 39042.9 , MSC 39042.10 , MSC 39042.11 , MSC 39042.13 , MSC 39053, GLS otolith comparative collection (11 specimens), WSU CC 473.3 , WSU CC 473.4 .

Description

Sagitta subcircular to subquadrate in outline. Height/length ratios exhibit considerable range related to increasing size. Smaller specimens (less than 2.5 mm) have ratios from around 65–75%; larger specimens (some exceed 12 mm) range from around 80–90%. Inner face convex, smooth. Margins smooth except for fine crenulations on very small juveniles. Dorsal margin nearly straight to somewhat arched. Conspicuous posterodorsal angle. Posterior margin straight to slightly curving inward; ventral margin broadly but unevenly rounded. Anterior margin evenly rounded. Very prominent heterosulcoid-type sulcus. Ostium filled with colliculum, moderately narrow, covers about 35% of length of inner face. Anterior of ostium even with anterior margin of sagitta. Dorsal and ventral margins of ostium essentially parallel anteriorly, but arch outwardly in posterior portion. Posterior margin of ostium nearly vertical. Cauda very long and narrow, has horizontal portion and sharply downturned portion. Horizontal portion of cauda significantly shorter than downturned portion, less excavated. Downturned portion of cauda more excavated, significantly longer, wider. Angle of horizontal and downturned portions around 90-degrees. Downturned portion almost reaches ventral margin. Outer face usually slightly concave, sculptured.

Remarks

Jefitchia copelandi has characteristics in common with Sciaena intermedius (see above), but J. copelandi is easily distinguished by its narrower ostium, and the dorsal and ventral margins of the ostium are essentially straight and parallel in the anterior portion ( Nolf 2013: pl. 281). Jefitchia copelandi is also similar to J. claybornensis (see below) but differs by the less elongate outline (higher height/length ratios) of J. copelandi , as well as by its much longer downturned portion of the cauda, and the angle of the downturned portion of the cauda (90-degrees or more from horizontal). The species appears to have a wide geographical range in the Eocene, as it is known from numerous locations in Alabama, Louisiana, Mississippi, Texas, and Virginia ( Frizzell & Dante 1965; Breard & Stringer 1999; Müller 1999).

Stratigraphic and geographic range in Alabama

Sagittae of J. copelandi have been recovered from the “upper” Lisbon Formation at site ACh-8 and the Gosport Sand at site AMo-4. Bartonian, zones NP16 and NP17.

Figures

Fig. 71. Claiborne Group, “upper” Lisbon Formation, otoliths. A–B. Lactarius kokeni Frizzell & Dante, 1965, MSC 39058. A. Inner face (right sagitta). B. Dorsal view. —C–D. Lactarius amplus Pomerol, 1973, MSC 39059. C. Inner face (left sagitta). D. Dorsal view. — E–F. Malacanthus? sulcatus (Koken, 1888), MSC 39061. E. Inner face (left sagitta, cauda worn). F. Dorsal view. — G–H. Orthopristis burlesonis Frizzell & Dante, 1965, MSC 39060. G. Inner face (left sagitta). H. Dorsal view. — I–J. Haemulon? obliquus (Müller, 1999), MSC 39062. I. Inner face (left sagitta). J. Dorsal view. — K–L. Anisotremus? sp., MSC 42236. K. Inner face (right sagitta). L. Dorsal view. — M–N. Percoidei, indet. 1, MSC 39063. M. Inner face (right sagitta). N. Dorsal view. — O–P. Sciaena intermedius (Koken, 1888), MSC 39050. O. Inner face (left sagitta). P. Dorsal view. — Q–R. Jeftichia copelandi Frizzell & Dante, 1965, MSC 39053. Q. Inner face (right sagitta, worn, especially anterior margin). R. Dorsal view. Scale bars: A–J, O–P=2 mm; K–L, Q–R =5 mm; M–N= 1 mm.