Hemilistrona homoirregularis (Ziegler, 1971) from the L.styriacus Zone at Ostrówka in the Holy Cross Mountains and Gołogłowy in the Sudetes.

Hemilistrona homoirregularis - P₁ and P₂ elements.

Diagnoza

Mature P₁ and P₂ element with posterior platform tongue bent downward and ornamented with tubercles.

Porównanie

A relatively large collection of this species from sample Ost-12 contains elements of various ontogenetic ages. Except for the mature P₁ elements, they show a puzzling variability in virtually all aspects of the platform shape and ornamentation. This is probably the most variable population of polygnathids in the Famennian of the Holy Cross Mts. There is a transition to morphologies classified here as Hemilistrona margaritata, Polygnathus? experplexus and even Neopolygnathus communis. Until population and apparatus studies on much larger and taxonomically less diverse material are performed, this classification can be treated only as provisional. 

Autekologia

Występowanie geograficzne

Ostrówka, Miedzianka, Gołogłowy, Kowala and Jabłonna.

Zasięg czasowy

P. trachytera to L. jugosus Zones. 

Materiały muzealne

ZPAL: 810 specimens.

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.