Ancyrodella rotundiloba (Bryant, 1921) from the Frasnian of Wietrznia  - P₁ elements.

Diagnoza

Porównanie

The apparatus was restored by Klapper & Philip (1972). In samples from the lower part of the Wietrznia I section robust P₂ elements are rather safely identifiable and only juvenile specimens can be misidentified with those of other polygnathids. The symmetry transition series specimens attributable to Ancyrodella bear relatively short processes. The dorsal process is usually bent basally. A characteristic feature is the hooked terminal end of the ventral process. However, the ramiform elements are highly variable and there is a continuous morphologic transition to the co-occurring robust polygnathids. Juvenile elements and some of adults can be only arbitrarily attributed taxonomically. This refers also to M  elements.

Autekologia

Występowanie geograficzne

Wietrznia, Czarnów,Śluchowice, Holy Cross Mts.

Zasięg czasowy

Frasnian

Materiały muzealne

ZPAL

Literatura

Dzik, J. 2002. Emergence and collapse of the Frasnian conodont and ammonoid communities in the Holy Cross Mountains, Poland. Acta Palaeontologica Polonica 47, 565-650.

Szulczewski, M. 1971.  Upper Devonian conodonts, stratigraphy and facies development in the Holy Cross Mts. Acta Geologica Polonica 21, 1-129.

Klapper , G. & Philip, G.M. 1972. Familial classification of reconstructed Devonian conodont apparatuses. Geologica et Palaeontologica SB 1, 97-114.