Walliserodus costatus Dzik, 1976 from the Mójcza Limestone at Mójcza, Holy Cross Mts.

Diagnoza

All the elements of the apparatus with relat vely shallow basal cavities (and consequently robust cusps). Longitudinal keels are very low and generally more numerous than in other species of the genus. In the symmetry transition series an almost symmetrical element type with convex external side.

Porównanie

The species differs from W. ethingtoni in a shallower basal cavity and less prominent longitudinal ribbing, from W. nakholmensis in convex external side of (almost) symmetrical elements.
The large element type (M) is of a Scalpellodus type and this, together with weak and numerous longitudinal keels in the remaining elements, suggests a close relationship or even derivation from the species Scalpellodus latus (van Wamel, 1974). The end member of the S series may be symmetrical but this remains unclear, as the only strictly symmetrical elements found (in sample Ma-I27) are of very small size. Their apparent symmetry may be due to the incomplete development of the keels. Morphologically the closest elements from other samples (mainly from Ma-128) are slightly asymmetric.

Autekologia

Występowanie geograficzne

Mójcza

Zasięg czasowy

The species appears at the base of the Mójcza limestone and occurs up to the
discontinuity surface (L. variabilis Zone, Kundan), known also in the latest Latorpian and Volkhovian of the Baltic region.

Materiały muzealne

ZPAL

Literatura

Dzik, J. 1994. Conodonts of the Mójcza Limestone. In: J. Dzik, E. Olempska, & A. Pisera. Ordovician carbonate platform of the Holy Cross Mountains. Palaeontologia Polonica 53, 43-128.