Recent discoveries of Tithonian ammonites in the Štramberk Limestone (Kotouč Quarry, Outer Western Carpathians)

Abstract

Recent discoveries of ammonites in the Štramberk Limestone in the type area of their occurrence near the town of Štramberk supplement existing data on the Tithonian age of the limestones. Franconites cf. fascipartitus occurs in the lower part of the Lower Tithonian (Neochetoceras mucronatum Zone). Lemencia ciliata has a zonal character in the upper part of the Lower Tithonian. Richterella richteri is a subzonal species of the upper part of the Lower Tithonian in the Mediterranean and Submediterranean areas (Semiformiceras fallauxi Zone). All of the new discoveries are referable to the faunal associations of the Submediterranean bioprovince, and are in agreement with existing knowledge of it. Sexual dimorphism was seen in the genus Richterella, with the recognition of both macroconchs and microconchs in the type species of Richterella, i.e. R. richteri. The stratigraphic position of these recent ammonite discoveries in the Štramberk Limestone at the Kotouč Quarry does not support the stratigraphy of the limestones based on the distribution of calpionellids, as previously assumed by other authors. The recent collection of ammonites confirms that the Štramberk Limestone belongs to the lower Tithonian and lower Berriasian and also represents the lower Tithonian as a shallow-water facies.