Dimeroceras globosoides (Sobolew, 1914) from the late C. marginifera Zone at Łagów in the Holy Cross Mountains.

Diagnoza

Suture with incipient umbonal lobe; juvenile conch globose with umbo about 3 mm wide; internal shell thickenings, if present, of radial course.

Porównanie

This is a relatively long-ranging lineage, in the P. trachytera Zone represented by Sobolew’s (1914) Oma-monomeroceras (Cheiloceras) globosum and possibly O. (Ch.) praeglobosum. The problematic O. (Ch.) umbiliferum has a better developed umbonal lobe and more evolute juvenile conch. An unnambered Otto Schindewolf ’s mature specimen from his “Schicht 2”, do not exposing suture but possibly belonging to this species, shows gradually opening umbilicus in the last half-whorl, reaching 85 mm in diameter.

Autekologia

Występowanie geograficzne

Łagów-Dule.

Zasięg czasowy

Late C. marginifera to P. trachytera Zones.

Materiały muzealne

ZPAL: 18 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.