Wormsipora sp.

Cui, Yu-Nong & Wang, Guang-Xu, 2023, Early Katian, Late Ordovician, heliolitine corals from southern Kuruktag in northeastern Tarim Basin of China, Acta Palaeontologica Polonica 68 (2), pp. 273-295 : 285-286

Wormsipora sp.

Fig. 10 .

Material.—One sectioned specimen, NIGP 201004, from the Yuanbaoshan Formation (lower Katian) of southern Kuruktag, Tarim Basin, China.

Description.—The corallum of low domical form, 37.07 mm wide and 14.06 mm high. Corallites slightly stellate, with TaDs 0.76–0.83 mm (average 0.81 mm). Corallite walls longitudinally plicated, 0.07–0.12 mm thick (average 0.08 mm). Septa 12 in number, each consisting of a series of discrete spines. Septal spines 0.15–0.22 mm long (average 0.18 mm), commonly extending no more than one-third the TaD. Tabulae complete, horizontal or slightly sagging or convex, Ta5 10–14. Corallites often in contact or separated by narrow coenenchyme, with their centers 0.84–1.08 mm apart (average 0.93 mm). Coenenchymal tubules weakly developed, commonly 0.17–0.22 mm in diameter (average 0.21 mm). Tubular walls discontinuous, 0.04–0.05 mm thick. Diaphragms complete, flat, slightly convex or oblique, mostly 24–26 per 5 mm.

Remarks.—The present specimen is characterized by small corallites and short septa, which distinguish it from other known Wormsipora forms, and may represent a new species. However, an open nomenclature is used due to limited material. It shows closest similarities to the type material of Wormsipora orientalis ( Yu, 1960) documented from the Hadabulaktag Formation (upper Katian) of northern Kurutag, Xinjiang, but is distinguished by much smaller corallites (0.76–0.83 mm in diameter), as well as more complete tabulae and tubular walls.

A comparison of Wormsipora sp. with similar species is shown in Table 3 and discussed below. Wormsipora hirsutus Lindström, 1899 ) from the Upper Ordovician of Sweden differs from Wormsipora sp. in having better developed coenenchyme and septal spines. Wormsipora hiruta minor White and Yang, 2004 , from the Upper Ordovician Glyn Limestone of North Wales, is separable by larger corallite size (1.3–1.5 mm in diameter) and more concave tabulae.

Figures

Fig. 10. Heliolitine tabulate coral Wormsipora sp. from the Yuanbaoshan Formation (lower Katian) of southern Kuruktag, Tarim Basin, Northwest China. NIGP 201004.A1, A2, transverse sections.A3, A4, longitudinal sections.