Orthopristis americana ( Koken, 1888 )

Lin, Chien-Hsiang & Nolf, Dirk, 2022, Middle and late Eocene fish otoliths from the eastern and southern USA, European Journal of Taxonomy 814, pp. 1-122 : 84

Orthopristis americana ( Koken, 1888)

Fig. 31A–D

Otolithus (Carangidarum) americanus Koken, 1888: 277 , pl. 17 figs 1–3.

“genus Pomadasyidarum ” americanus – Nolf 1985: 86.

Orthopristis americana – Nolf & Stringer 2003: 6, pl. 4 figs 17–21. — Nolf 2003: 6, pl. 3 figs 13–15; 2013: 101, pl. 252. — Stringer et al. 2022: 7, fig. 3i.

Remarks

Two closely related congeneric species, O. americana and O. burlesonis (Dante & Frizzell, 1965) , exist in our collection. However, they are both morphologically and chronologically distinct: O. americana has more compact otoliths with a deeper ventral area, whereas the otoliths of the latter species are more elongate, which is due to their extended posterior part. The occurrence of O. americana is restricted to the younger Moodys Branch Formation and Yazoo Clay, and O. burlesonis is only found in the older Claiborne Group.

Stratigraphic and geographic distribution

Bartonian: Moodys Branch Formation, Louisiana, Mississippi and Alabama. Priabonian: Yazoo Clay, Louisiana.

Figures

Fig. 31. Fish otoliths from the US middle and upper Eocene.A–D. Orthopristis americana (Koken, 1888), Moodys Branch F., Jackson, Riverside Park, Mississippi (IRSNB P 10198–10201). E–F. Orthopristis burlesonis (Dante & Frizzell, 1965), “Stone City beds”, Stone City Bluff, Brazos River, sample 2 from bed P, Texas (IRSNB P 10202–10203). 1 = ventral view; 2 = inner view. Scale bars = 1 mm.