The earliest gastropod with varices from the Mesozoic and the first record of decapod crustaceans from the St. Cassian Formation, Dolomites, Italy-a possible example of Triassic predator- prey interaction

Nützel, Alexander; Schweigert, Guenter und Karapunar, Baran (2022): The earliest gastropod with varices from the Mesozoic and the first record of decapod crustaceans from the St. Cassian Formation, Dolomites, Italy-a possible example of Triassic predator- prey interaction. In: Neues Jahrbuch für Geologie und Paläontologie / Abhandlungen, Bd. 305, Nr. 2: S. 153-160

Abstract

A new seguenziid gastropod, Varicoturbo microstriatus n. gen. n. sp., is described from the Upper Triassic (lower Carnian) St. Cassian Formation (Dolomites, Italy). This species is remark-able because it is the first known Triassic gastropod that has multiple distinct shell varices, a mor-phological feature that becomes common from the Cretaceous onwards and is considered to be an anti-predatory adaptation. Durophagous predators are very rare in the sediments of the St. Cassian Formation -only scarce fish and placodont remains belonging to this guild have been reported. How-ever, fragments of crustacean appendages are reported here from the St. Cassian Formation for the first time. The fragments represent chelae fingers and pereiopod articles of decapod crustaceans, most likely of anomuran affinity. Molariform teeth on the occlusal surfaces of the fingers likely indicate a crushing function. These new findings might represent some the earliest crushing and anti-predatory adaptations exhibited by crustaceans and molluscs long before this predator- prey relationship was well established between the decapods and molluscs. These features are also unique in being present at a very small size range (0.5-5 mm).

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Geowissenschaften > Department für Geo- und Umweltwissenschaften
• Themengebiete: 500 Naturwissenschaften und Mathematik > 550 Geowissenschaften, Geologie
• ISSN: 0077-7749
• Sprache: Englisch