Protornoceras curvidorsatum (Sobolew, 1914) from the P. trachytera Zone at Łagów-Dule in the Holy Cross Mountains.

Diagnoza

Evolute conch with umbo width approaching one third of its diameter; subtrapezoidal cross section of the whorl; more or less simplified suture.

Porównanie

Only juvenile specimens exhibit suture, which appears to be extremely simplified. Growth lines are prominent, in one specimen numerous apertural thickenings developed along its venter. From the geologically older P. mirabile the species differs in the narrower umbo and higher whorls. Possibly some other taxa  on the Łagów-Dule clymeniid limestone belong here: Gomi-re-monomeroceras (Tornoceras) planilobum arcuatolobatum, G. (T.) sinuvaricatum, and G. (T.) umbilicatoides.

Autekologia

Występowanie geograficzne

at Łagów-Dule; possibly also reworked at Sieklucki’s brickpit in Kielce.

Zasięg czasowy

P. trachytera Zone (sample Ł-14). 

Materiały muzealne

ZPAL: 10 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.