Biskupič R., 2020: Early ontogeny, paleoecology and intraspecific variability of two Helminthia species (Gastropoda: Turritellidae) from the Middle Miocene (Badenian) deposits of the eastern Vienna Basin (Slovakia). Acta Geologica Slovaca, 12, 2, 75–88.

Early ontogeny, paleoecology and intraspecific variability of two Helminthia species (Gastropoda: Turritellidae) from the Middle Miocene (Badenian) deposits of the eastern Vienna Basin (Slovakia)

Radoslav Biskupič

Ludvíka Svobodu 29, 058 01 Poprad, Slovakia; biskupic.radoslav@gmail.com

Abstract

In this study, a new evidence of Neogastropods of the family Costellariidae MacDonald, 1860 from the Miocene of Central Paratethys is presented. The finds of fossil shells of the genus Vexillum Röding, 1798 derives from the middle Miocene (Serravallian) marine deposits from the eastern margin of the Vienna Basin (Western Carpathians, Slovakia), which belongs to the north-west Central Paratethys realm. The studied gastropods were discovered at the locality Rohožník – Konopiská, in the basinal pelitic facies and organodetritic corallinacean marls of the Studienka Formation of late Badenian age (Bulimina-Bolivina Biozone). The material studied here includes two new species: Vexillum svagrovskyi sp. nov. and Vexillum pseudoschafferi sp. nov. The affinity and comparison of both species with other similar costellariids from the Neogene of European Eastern Atlantic, Proto-Mediterranean and Paratethyan regions are discussed. From a paleoecological point of view, the results suggest that V. svagrovskyi was adapted to a moderately deep, circalittoral environment with occasional worsening of the paleoecological conditions (low bottom water oxygenation), whereas species V. pseudoschafferi preferred a shallow-water infralittoral environment.

Key words: Vexillum, Costellariidae, Gastropoda, Miocene, Badenian, Vienna Basin, Slovakia

Manuscript received: 2020-04-17

Revised version accepted: 2020-10-18