Dataset to: Stumpf et al. (2026) "First hybodontiform record reveals chondrichthyan role in Carnian food webs of the Upper Triassic Reifling Basin, Austria"

MicroCT dataset used in the publication "First hybodontiform record reveals chondrichthyan role in Carnian food webs of the Upper Triassic Reifling Basin, Austria" by Sebastian Stumpf, Alexander Lukeneder and Viola Winkler.

The Upper Triassic Reifling Basin of the Northern Calcareous Alps in Austria has yielded rich marine fossil assemblages, offering rare insights into complex basinal food webs during the Carnian Pluvial Event (CPE), a critical interval of major global environmental upheaval. Despite extensive sampling, chondrichthyan fishes had not been recovered until now. Here we report the first unambiguous chondrichthyan record from the Reifling Basin, represented by a single indeterminate hybodontiform tooth from the lower Carnian of Scheiblingbach. Still largely embedded in matrix, the specimen was examined through micro-CT scanning and digital segmentation. The tooth, indicative of a small- to medium-sized durophagous generalist likely occupying a mid-trophic position, adds to the scarce chondrichthyan record from the Alpine Upper Triassic during the CPE. While the Scheiblingbach tooth bears some resemblance to Polyacrodus and Acrodus, the deeply unresolved taxonomy and likely polyphyletic nature of these and other historically problematic hybodontiform genera preclude confident identification, exemplifying the persistent difficulty of assigning isolated hybodontiform teeth to specific taxa. Nonetheless, the tooth from Scheiblingbach refines our understanding of Triassic hybodontiform diversity and distribution and highlights the urgent need for future research to overcome long-lasting taxonomic challenges that continue to constrain our perception of early Mesozoic chondrichthyan dynamics.

MicroCT system: YXLON FF35 CT, FXE Direct Beam, Perkin Elmer Y.Panel 4343 CT

Current: 160 µA

Voltage: 120 kV

3600 projection images, 2 s each

Reconstructed isotropic voxel size: 6.4 µm