Signata nicoli Dante & Frizzell, 1965

Fig. 38I

Signata nicoli Dante & Frizzell in Frizzell & Dante, 1965: 709, pl. 88 figs 3–4, 21, 25.

Signata nicoli – Schwarzhans 1981b: 113. — Ebersole et al. 2019: 200, fig. 70i–j.

“genus Ophidiidarum ” nicoli – Nolf 1985: 67.

“ Ophidiida ” nicoli – Nolf 2013: 65, pl. 124.

Remarks

Signata represents yet another extinct taxon within Ophidiidae. The otoliths have a very wide sulcus that is filled only with a very flat, undivided colliculum. This sulcus has a somewhat Sirembo -like aspect, but the stronger convexity of the inner face and the more extended and thinner posterior part are never seen in Sirembo or any other related otolith type. Also, in otoliths of Signata, the areas above and below the sulcus are very restricted. Otoliths of Signata are very well characterized by autapomorphic features, but do not provide any indication for affinities with other ophidiid groups. Two species are included in the genus: S. nicoli and S. stenzeli. The holotype of S. nicoli has smoothly curved cristae, with just an angle on the crista superior, while the otoliths of S. stenzeli have a more elevated angle on the crista superior and two notable undulations in their crista inferior. The holotype of S. nicoli is from the Weches Formation (Lutetian) of Texas, but we did not find additional specimens among our present collection. Ebersole et al. (2019), however, reported a specimen from the “upper” Lisbon Formation (Bartonian) of Alabama.

Stratigraphic and geographic distribution

Lutetian: Weches Formation, Texas. Bartonian: “upper” Lisbon Formation, Alabama.