Data from: A peculiar tooth renewal in a Jurassic ray-finned fish (Lepisosteiformes: †Scheenstia sp.)
Leuzinger, Léa; Cavin, Lionel; López-Arbarello, Adriana; Billon-Bruyat, Jean-Paul (2019), Data from: A peculiar tooth renewal in a Jurassic ray-finned fish (Lepisosteiformes: †Scheenstia sp.), Dryad, Dataset, https://doi.org/10.5061/dryad.82r11rm
Tooth replacement in vertebrates is extremely diverse, and its study in extinct taxa gives insights into the evolution of the different dental renewal modes. Based on µ-CT scans of a left lower jaw of the extinct fish †Scheenstia (Actinopterygii – Lepisosteiformes), we describe in detail a peculiar tooth replacement mode that is, as far as we could trace back in the literature, unique among vertebrates. The formation of the replacement teeth comprises a 180° rotation of their acrodin cap that occurs intraosseously within bony crypts, and their setting up appears to be synchronous. We propose a model for the dental renewal process, and identify complementary anatomical features visible in the tomography such as the junction between the different tooth-bearing bones (prearticular-coronoid and dentary), as well as cavities corresponding to intraosseous crypts, nervous and/or vascular canals. The location of the cavities and their subsequent identification (e.g. Meckel’s cavity, mandibular sensory canal) help settling the function of pores visible on the bone surface and understanding their relation to internal anatomical features. Finally, this tooth replacement mode raises the question whether it is specific to †Scheenstia or rather related to a particular dentition type and thus potentially occurs in other lineages.
canton of Jura