Abstract

Abundant well-preserved isolated asteroid ossicles are described from the Carnian Stage (Julian Substage) Cassian Formation of South Tyrol, northeast Italy. Detailed study of articulation surfaces and external sculpture, aided by comparison with articulated specimens of related taxa from the German Muschelkalk (Anisian– Ladinian) indicates that three species are present, here assigned to Cortinaster papillifera gen. et sp. nov. (type species), Cortinaster zardinii gen. et sp. nov., and Soleaaster thuyi gen. et sp. nov. It is concluded that all belong to the Triassic asteroid order Trichasteropsida Blake, 1987, but they display remarkable variation in the morphology of the adambulacral ossicles which, in two of the species, possess characters comparable to those of some Late Palaeozoic asteroids. The third species has adambulacral structure essentially similar to taxa of the post-Triassic order Valvatida Perrier, 1884. The diversity of Triassic asteroids is reviewed, and a new genus, Hagdornaster gen. nov. with the type species H. bieletorum (Blake and Hagdorn, 2003), is described from the German Muschelkalk.

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