Protopanderodus gradatus Serpagli, 1974 from the Mójcza limestone.

Apparatus of Protopanderodus gradatus Serpagli, 1974.

Diagnoza

The M elements have a shallow furrow on the posterior surface along the external margin. In other elements, deep furrows split the flanks into rounded ribs.

Porównanie

The type population of the species is the oldest one known (early Volkhovian) and it seems to have primitive morphologic features that are mainly expressed in less sinuous bases of the elements than in younger (early Kundan) populations. Otherwise all the element types in the Argentina population seem to be virtually identical with those in the Baltic and Polish ones.

Autekologia

Występowanie geograficzne

Zasięg czasowy

Occurs somewhat irregularly in the Mójcza limestone from 0.7 m below the
discontinuity surface (L. variabilis Zone) up to 1.2 m below the bentonite (E.lindstroemi Subzone).
In Argentina and Newfoundland known from slightly older strata of Volkhovian age.

Materiały muzealne

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.