Article ID Journal Published Year Pages File Type
4747318 Cretaceous Research 2012 6 Pages PDF
Abstract

A small faunule of the calcareous sponge Porosphaera globularis ( Phillips, 1829) (Calcarea, Minchinellidae) is described and illustrated from the Maastrichtian Farokhi Formation of Central Iran. The shape of the sponges varies from near-spherical to pyriform with diameters ranging between 5 and 13 mm. The surfaces show small, equidistant apertures corresponding to radiating oscular tubes within a choanosomal skeleton consisting of large tetractines fused to a rigid framework. Radially arranged superficial grooves may also be present in some specimens. External attachment scars have not been observed, but perforations in two specimens may represent sipunculan worm borings. A quiet and fairly deep-water environment can be inferred as the habitat of the sponges, corresponding to data in the literature. So far, P. globularis was known only from the Upper Cretaceous (Cenomanian–Maastrichtian) of the Boreal Realm. The record from Central Iran is the southernmost occurrence of P. globularis (palaeo-latitude ca. 20°N) known to date and is the first description of the species from Iran and the Middle East.

► Porosphaera globularis ( Phillips, 1829) (Calcarea, Minchinellidae) occurs in Iran. ► It was collected from the Maastrichtian (Farokhi Formation) of Central Iran. ► The occurrence corresponds to a subtropical warm-water environment. ► P. globularis is mainly known from Boreal Late Cretaceous shelf seas in Europe. ► This is the first record of P. globularis from Iran (and the Middle East).

Related Topics
Physical Sciences and Engineering Earth and Planetary Sciences Palaeontology
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