Platform-bearing derivative of Mehlina, Polynodosus lauriformis (Dreesen & Dusar, 1974)   from the L. styriacus Zone at Ostrówka  in the Holy Cross Mountains.

Polynodosus lauriformis (Dreesen & Dusar, 1974) from the L. styriacus Zone at Ściegnia - P₁ and P₂ elaments.

Polynodosus lauriformis - P₁ and P₂ elements.

Diagnoza

Laurus leaf-shaped platform ornamented with nodes, restricted to its margin in juvenile specimens and covering the whole platform surface in adults.

Porównanie

From the coeval Lagovignathus fallax differs in the coarse ornamentation of the platform and the composition of the apparatus, from its probable ancestor P. transitus in a more regular outline of the platform. In samples Ł-24 and Ł-26 specimens morphologically indistinguishable from P. lauriformis  co-occur with those of P. transitus and transitional specimens are rare. Whether these are sympatric species or just a case of population variability, remains to be clarified. There is a possibility that P. lauriformis is a more off-shore counterpart of P. transitus.

Autekologia

Występowanie geograficzne

Kowala, Wzdół Plebański (Ściegnia), Miedzianka, and Ostrówka.

Zasięg czasowy

From the C. marginifera to L. styriacus Zones.

Materiały muzealne

ZPAL: 367 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.