Cyrtospiriferidae Termier and Termier, 1949

Halamski, Adam T. & Baliński, Andrzej, 2009, Latest Famennian brachiopods from Kowala, Holy Cross Mountains, Poland, Acta Palaeontologica Polonica 54 (2), pp. 289-306 : 300

Family Cyrtospiriferidae Termier and Termier, 1949 Cyrtospiriferidae gen. et sp. indet.

Fig. 9G.

Material.—One shell ZPAL Bp 57/10, lacking postero−lateral parts, otherwise well preserved.

Description.—Shell 14.3 mm long, transverse, strongly ventribiconvex. Cardinal margin straight. Dorsal fold distinct but low and flattened. Ventral sulcus distinct but shallow. Ventral interarea apsacline, incurved, transversely striate; delthyrium 4.2 mm wide; remnant of a convex pseudodeltidium is visible. Dorsal interarea linear, catacline. Anterior commissure uniplicate, tongue rounded, 9.1 mm wide. Ornamentation of radial costae and costellae separated by narrower furrows, 10 on dorsal lateral flanks, 14 on ventral lateral flanks, 10 in fold and sulcus. Sinal pattern with numerous main plications, one group of densely crowded central plications and rare lateral plications ( Fig. 9G 6 ). Fold pattern poorly preserved, with more dense central plications ( Fig. 9G 1). Micro−ornamentation of fine radial capillae both on costae and between them ( Fig. 9G 7 ), preserved in the ventral sulcus only.

Interior unknown.

Remarks.—The general form and sinal pattern of the discussed specimen remind of Sinospirifer Grabau, 1931 ; on the contrary, the micro−ornamentation is strongly similar to the davidsoni −pattern sensu Ma and Day (2007), characteristic of Cyrtiopsis . The form cannot be determined taxonomically with confidence due to inadequate preservation of the studied material (in particular, absence of internal characters).

Figures

Fig. 6. Transverse serial sections of Novaplatirostrum sauerlandense Sartenaer, 1997 through shell ZPAL Bp 57/40 from Kowala, set L. Numbers indicate distances in mm from ventral umbo.

Fig. 7. Middle to Latest Famennian brachiopods from Kowala. A–D. Novaplatirostrum sauerlandense Sartenaer, 1997; four shells ZPAL Bp 57/106, 39, 38, and 105, respectively, in dorsal (A1, B1, C1, D1), ventral (A2, B2, C2, D2), lateral (A3, B3, C3, D3), posterior (A4, B4, C4, D4), and anterior (A5, B5, C5, D5) views. E. Hadyrhyncha sp.; shell ZPAL Bp 57/115 in dorsal (E1), ventral (E2), lateral (E3), posterior (E4), and anterior (E5) views. F, G. Centrorhynchus sp.; external imprints ZPAL Bp 57/61 and 62, respectively, of two strongly flattened ventral valves on a shale surface.