Cymaclymenia costellata (Münster, 1832) from the D. trigonica Zone at Kowala in the Holy Cross Mountains.

Diagnoza

Aperture with somewhat angular convexity on flanks and relatively sharply delimited deep ventral sinus; umbo covering one fourth of the conch diameter in adult conchs.

Porównanie

Specimens from the same strata classified  in C. compressa (Münster, 1832) belong here. The type specimen of this species is too poorly preserved to be identifiable. Czarnocki’s specimens come from the red marly limestone and have unusully well preserved, as for the locality, shells. No similar material has been encountered later, which may mean that they occurred in a lens of restricted extend. The sample seems thus homogenous and shows the actual range of variability. It is expressed not only in the conch proportion, but also in the shape of aperture, believed to be of high diagnostic value. The course of growth lines may dramatically differ even in different parts of the same conch.

Autekologia

Występowanie geograficzne

Kowala. 

Zasięg czasowy

D. trigonica Zone. 

Materiały muzealne

ZPAL: 23 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.