Conifer Diversity in the Middle Triassic: New Data from the Fossillagerstätte Kühwiesenkopf/Monte Prà della Vacca (Pelsonian, Anisian) in the Dolomites (Northeastern Italy)

Abstract

Premise of research. The Triassic is considered a pivotal time for the radiation of modern conifer families. In this article, we describe the conifers from the Fossillagerstatte Kuhwiesenkopf/Monte Pra della Vacca, emending already known taxa and proposing a new species (Voltzia edithae sp. nov.). Moreover, we provide a picture of the chronostratigraphic and geographic distribution of the Middle Triassic conifer shoots of Europe. Methodology. The macromorphology and cuticles of the vegetative conifer organs are described, and the stratigraphic and geographic distribution pattern of the Middle Triassic conifer shoots in European is evidenced. Pivotal results. Six different conifer species are identified among the conifer shoots of the Kuhwiesenkopf flora. Morphological analyses of our material of Albertia cf. latifolia show that the previously described species A. latifolia, A. elliptica, A. braunii, and A. speciosa probably fall within the natural variability of one species, but this has to be validated by the revision of the original specimens. The occurrence of V. heterophylla in the Kuhwiesenkopf flora extends its geographic range to the Alpine Realm. An emended diagnosis is proposed for V. walchiaeformis based on well-preserved specimens, including cuticle fragments. The new species V. edithae sp. nov. shows significant morphological similarities to the late Permian Majonica alpina and the Middle-Late Triassic V. foetterlei. Conclusions. The conifers of the Kuhwiesenkopf flora are unique for the Middle Triassic of Europe in their richness and diversity. The conifers are a mixture of typical Early-Middle Triassic taxa (Pelourdea vogesiaca, V. heterophylla, V. recubariensis), Anisian taxa (V. walchiaeformis), and a new species (V. edithae sp. nov.) that is seen as a transitional form sharing morphological characters with both late Permian and Middle-Late Triassic conifers.