Diagnoza

P₁ elements with a ridge along the anterior margin of the platform, ventrally departing from the blade and truncated with an angulation perpendicular to it.

Porównanie

In several large samples studied there is a complete gradation between morphologies traditionally believed to characterize separate species, including ‘Palmatolepis’ prima, ‘P.’ pectinata or ‘P.’ acuta. I consider them variants within population variability, although the type populations of some of them may truly be distinct from C. glabra.

Elements of the apparatus of this species are closely similar to those of C. quadrantinodosa and it is difficult to separate them in samples. The difference is that in C. glabra P₂ elements are more arched and M elements more elongated than in the other lineage.

The species is apparently ancestral to C. distorta and probably to C. falcata. Evolution from C. prima to C. glabra and from C. glabra to C. distorta is connected with increased variability and transitional populations are polymorphic in respect to morphology of P₁ elements. Delimitation of these probable chronospecies is thus rather conventional.

Autekologia

Występowanie geograficzne

Łagów, Kowala, Jabłonna, and Miedzianka; also in the Dębnik area.

Zasięg czasowy

C. quadrantinodosa Zone.  

Materiały muzealne

ZPAL: 2,230 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.