Squatinactis caudispinatus Lund and Zangerl, 1974

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 : 915

Squatinactis caudispinatus Lund and Zangerl, 1974

Figs. 7G , 8D .

Material.—Four teeth from upper Viséan of Cawdor Quarry, Matlock, Derbyshire, England, UK (samples Cawdor 5 and 11); NHMUK PV P73282, NHMUK PV P73286.

Description and remarks.—A few small cladodont teeth (less than 0.5 mm across the base) from Cawdor Quarry are tentatively attributed to S. caudispinatus because of the short base (labio-lingually) provided with two separate, oval orolingual buttons and two basolabial projections, separated by a deep basolabial depression. Some of the teeth are wide (mesio- -distally) and have multicuspid crowns (up to four lateral cusps; Fig. 8B ), covered on both sides with sub-parallel cristae, and the other have narrower bases ( Fig. 7G ), fewer cusps and apparently less well developed ornamentation. Similar differences were observed in the material of S. caudispinatus from the Tournaisian of Illinois, USA (Ginter et al. 2010: fig. 73A–F).

Stratigraphic and geographic range.—Articulated specimens from Serpukhovian of Bear Gulch, Montana, USA ( Lund and Zangerl 1974; Lund 1988), Tournaisian of Illinois, USA (Ginter et al. 2010) and South Urals, Russia (Ivanov 1996), upper Viséan of Derbyshire, England (this paper).

Figures

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.

Fig. 8. Chondrichthyan teeth from the upper Viséan of Cawdor Quarry, Matlock, Derbyshire, England, UK; sample Cawdor 5 (A–E), 8 (F). A. Bransonella nebraskensis (Johnson, 1984), NHMUK PV P73283, in lingual (A 1), labial (A 2), and oral (A 3) views. B. Squatinactis caudispinatus Lund and Zangerl, 1974, NHMUK PV P73286, in labial (B 1) and oblique lateral (B 2) views. C, D. Cooleyella fordi (Duffin and Ward, 1983). C. NHMUK PV P73284, in oral C 1) and lingual (C 2) views. D. NHMUK PV P73285, in aboral/labial view. E. Ginteria fungiforma Duffin and Ivanov, 2008, NHMUK PV P66676, in oral E ), lateral (E ), and lingual (E ) views. F. Tip of a helodontid holocephalian tooth, NHMUK PV P73287, in lateral view.