Original paper
Calcareous algae and foraminifers across the Permian-Triassic boundary interval (uppermost Bellerophon Formation and basal Werfen Formation) in the Dolomites (South Tyrol – Trentino, Italy)
Vachard, Daniel; Krainer, Karl
Palaeontographica Abteilung A Band 324 Lieferung 1-6 (2022), p. 1 - 173
673 references
published: Oct 13, 2022
published online: Jul 4, 2022
manuscript accepted: Mar 22, 2022
manuscript received: Dec 21, 2021
Abstract
Three measured sections (Seres A and B, and Göma) have been studied in the Peitlerkofel/Sass de Putia (2875 m a.s.l.) massif in the northwestern Dolomites (South Tyrol/Northern Italy) and one section at a small gorge near Gabbiolo about 3 km SE of Trento (Italy). These sections exhibit the Permian-Triassic boundary interval in the uppermost Bellerophon Formation (including the Bulla Member) and lower Werfen Formation (Tesero Member and basal Mazzin Member). Four assemblages of foraminifers and calcareous algae are defined, which correspond respectively to the early or late Changhsingian; late Changhsingian; latest Changhsingian; and earliest Triassic. Most interesting cyanobacteria and calcareous algae are Cayeuxia alpina Boueina? cf. tubulata, classical gymnocodiaceans, and dasycladalean algae Aciculella preromangica Atractyliopsis lastensis Eogoniolina johnsoni Mizzia velebitana Physoporella laevis, and Succodium luciae n. sp. Eogoniolina is relatively abundant, whereas Mizzia is rare. Some Calcitarcha (incertae sedis) are noticeable: Calcisphaera?, Bituberitina?, Eotuberitina Eotubespina n. gen., and Floritheca. The plurilocular Fusulinata belong principally to Globivalvulina and Charliella, especially Charliella dolomitica n. sp., and to the nankinellid Hayasakaina cf. paraminor. Miliolata are represented by calcivertellids Planiinvoluta, hemigordiids Hemigordius, and neodiscids Multidiscella n. gen., Midiella, and Pseudomidiella. The lineage which encompasses the genera Postcladella Praetriadodiscus Rectoglomospira Semimeandrospira Planiinvoluta?, Pilammina?, and Hoyenella, seems to be transitional between the foraminiferal classes Miliolata and Involutinata. The Nodosariata are composed of Rectostipulina Nodosinelloides Polarisella Nestellorella Pseudolangella?, Langella?; Geinitzina Neogeinitzina Praerectoglandulina Frondinodosaria Calvezina Ichthyofrondina Pachyphloia, and Aulacophloia. New taxa are Multidiscinae n. subfam.; Multidiscella langei n. sp.; M. zaninettiae n. sp.; Postcladella giaccobei n. sp.; and Hoyenella annulata n. sp.
Keywords
Calcareous algae • foraminifers • taxonomy • biostratigraphy • Permian-Triassic boundary Interval • Northwestern Dolomites • Italy