Baltoniodus prevariabilis (Fåhræus, 1966) from the Mójcza Limestone.

Apparatus of Baltoniodus prevariabilis (Fahraeus, 1966).

Diagnoza

The S₃ and S₄ elements almost indistinguishable from each other, both having rudimentary anterior process, P₁ elements with a thin-walled triangular expansion at the base of the inner process.

Porównanie

Juvenile P₁ elements of this species have considerably longer processes than those of B. parvidentatus. The shape of the expansion of the base is highly variable within populations. The S₃ and S₄ elements, although closely similar in outline, can be distinguished owing to a different profile of the rudiment of the anterior process. In the S₃ elements the rudiment of the anterior process is unified with the inner margin of the external process and its surface is somewhat angular. In the S₄ elements the process is more or less parabolic in outline and located in between the remaining processes.

Autekologia

Występowanie geograficzne

Ordovician temperate climate zone.

Zasięg czasowy

In Mójcza the species occurs from the discontinuity surface up to 0.2 m above
the bentonite; elsewhere in the Late Llanvirn and Llandeilo.

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.