The Kungurian (lower Permian) plant fossil assemblage of Sinich/Sinigo (NE Italy)

The sedimentary succession of the Sinich/Sinigo Basin is one of the oldest sedimentary intercalations of the Cisuralian (lower Permian) Athesian Volcanic Group of the Bozen/Bolzano area. The plant remains that were deposited in its alluvial and lacustrine sediments are middle Kungurian in age and are characterized by a wide variety of preservation types. The nearly 600 specimens from Sinich/Sinigo include permineralized stems, compressions/impressions and casts/molds, which belong to various plant groups, such as putative lycopsids, sphenophytes, ferns, seed ferns, cordaitaleans and conifers. Strata of the Sinich/Sinigo Basin yield one of the richest and best-documented Kungurian plant assemblages of eastern paleoequatorial Pangea. The conifers are represented by both walchian and more derived voltzian Voltziales, forming the earliest co-occurrence of these two groups in eastern Pangea. The three-dimensional preservation mode revealed xeromorphic features in more than one conifer species, such as the presence of fleshy and deciduous leaves in both walchian and voltzian conifers. These morphological features were probably more common during the early Permian, being an adaptation to aridity. The comparison of the Sinich/Sinigo collection with other Kungurian plant assemblages strengthens the assumption of more widespread semi-arid to arid conditions in the middle-late Kungurian of the Southern Alps, whereas the strata and the presence of hygrophytic elements indicate that increased rainfall and flooding events could have occasionally occurred.

Automated summary

The Sinich/Sinigo Basin sedimentary succession is one of the oldest sedimentary deposits in the Cisuralian Athesian Volcanic Group. It contains well-preserved middle Kungurian plant remains that represent a diverse range of plant groups. The presence of both walchian and voltzian Voltziales in this basin suggests the early co-occurrence and adaptation to aridity.