Denaea williamsi Ginter and Hansen, 2010

Ginter, Michał, Duffin, Christopher J., Dean, Mark T. & Korn, Dieter, 2015, Late Viséan pelagic chondrichthyans from northern Europe, Acta Palaeontologica Polonica 60 (4), pp. 899-922 : 913-914

Denaea williamsi Ginter and Hansen, 2010

Fig. 13E, F .

2000 Denaea sp. ; Savitskiy et al. 2000: 49–50, pl. 16: 2–4.

2010 Denaea sp. nov B Ginter and Hansen (in press); Ginter et al. 2010: fig. 62.

2010 Denaea williamsi sp. nov.; Ginter and Hansen 2010: 34–36, figs. 3, 4.

Material.—Five teeth from upper Viséan of Todowa Grząba, north of Ostrówka Quarry, Gałęzice Region, Holy Cross Mountains, Poland (sample TG-D); MWGUW /Ps/11/18–19.

Description and remarks.—The teeth of D. williamsi from Todowa Grząba are very similar to those from the type material for the genus (Serpukhovian of Illinois, USA; Ginter and Hansen 2010: figs. 3, 4). They possess the specific ornament of the median cusp, composed of cristae which, on the labial side, diverge laterally at the base and then corresponding pairs join before reaching the tip, whereas on the lingual face they converge at various heights. The outermost cusps are strongly divergent, more so than in D. cf. fournieri . The base is provided with a distinct button, in the shape of horizontal figure of 8, at the lingual rim. However, whereas in the type material there are apparently only two large openings of the main basal canal, one in the centre of the aboral surface and another on the lingual rim, in at least one specimen from Todowa Grząba ( Fig. 13E ) an additional foramen is located between the button and the median cusp, as in smaller specimens of D. cf. fournieri ( Fig. 7F ).

The teeth from Todowa Grząba are small (0.5 mm across the base) and five-cusped. It seems that the seven-cusped tooth-crown of D. williamsi noted from Illinois, USA ( Ginter and Hansen 2010: fig. 4D) was an anomaly, probably occurring only in the largest specimens.

Stratigraphic and geographic range.—Viséan of the Moscow Syneclise ( Savitskiy et al. 2000), lower Serpukhovian of Illinois, USA ( Ginter and Hansen 2010), and upper Viséan of the Holy Cross Mountains, Poland (this paper). Similar, but not identical teeth from Serpukhovian/Bashkirian boundary beds of South Tien-Shan, Uzbekistan, were designated as Denaea cf. D. williamsi by Ivanov (2013),

Figures

Fig. 13. Cladodont teeth from the upper Viséan of Todowa Grząba, north of Ostrówka Quarry, Gałęzice Region, Holy Cross Mountains, Poland. A–D. Denaea wangi Wang, Jin, and Wang, 2004. A. MWGUW/Ps/7/6, in labial (A 1), oral (A 2), and lingual (A 3) views. B. ZPAL P.IV/224, in lingual (B 1) and oral (B 2) views. C. ZPAL P.IV/223, in lateral (C 1) and oral (C 2) views. D. ZPAL P.IV/222, in lingual (D 1) and oral (D 2) views. E, F. Denaea williamsi Ginter and Hansen, 2010. E. MWGUW/Ps/11/18, in lingual (E 1), labial (E 2), lateral (E 3), and oral (E 4) views. F. MWGUW/Ps/11/19, tooth with two cusps broken off in lingual view. G. Ctenacanthidae gen. et sp. indet., MWGUW/Ps/11/20, in lingual (G ), oral (G ), and labial (G ) views.

Fig. 7. Cladodont teeth from the upper Viséan of Cawdor Quarry, Matlock, Derbyshire, England, UK; sample Cawdor 9 (A–C), 11 (D–G). A–F. Denaea cf. fournieri Pruvost, 1922. A. NHMUK PV P73276, in lateral (A 1), oral (A 2), lingual (A 3), and labial (A 4) views. B. NHMUK PV P73277, in oral (B 1) and lingual (B 2) views. C. NHMUK PV P73278, in aboral (C 1) and aboral/labial (C 2) views. D. NHMUK PV P73279, in labial (D 1), oral (D 2), and oblique lingual (D 3) views. E. NHMUK PV P73280, in aboral (E 1) and labial (E 2) views. F. NHMUK PV P73281, in oral (F 1) and lingual (F 2) views. G. Squatinactis caudispinatus Lund and Zangerl, 1974, narrow tooth with broken base (NHMUK PV P73282), in labial (G ), oral (G ), and lingual (G ) views.