Mitrellataxis circularis (Wang et Wang, 1978) from thle L. styriacus Zone at Ostrówka (sample Ost-12): specimens ZPAL c XVI/ 1578-1580

Diagnoza

Cusp with oval cross section, elements variable in shape but not forming discrete morphologic classes, shallow basal cavity usually filled with tissue.

Porównanie

Despite general similarity of smooth elements, relationship of this species to Jablonnodus is not likely because they do not group in any recurrent morphologic classes. They rather resemble in colour and shape cusps and denticles of associated robust prioniodinids. It cannot be excluded that this is actually a prioniodinid with uncalcified bases of processes. That these were truly denticles of uncalcified processes of icriodontids or prioniodinids is supported by the linear elongation of the basal body, with a longitudinal furrow.

The only illustrated specimen of Drepanodus circularis Wang et Wang, 1978 has a short cusp, which makes it similar to M. conoidalis sp. n., so the taxonomic identification proposed here requires confirmation by the Chinese topotype material.

Autekologia

Występowanie geograficzne

Ranges from the late K. triangularis Zone to the top of the Famennian in almost all localities.

Zasięg czasowy

Materiały muzealne

3,295 specimens ZPAL

Literatura

Dzik, J. 2006. The Famennian "Golden Age" of conodonts and ammonoids in the Polish part of the Variscan sea. Palaeontologia Polonica 63, 1-359.