The first Record of Plicidentine in Varanopseidae (Synapsida, Pelycosauria)

The first Record of Plicidentine in Varanopseidae (Synapsida, Pelycosauria)

Michael Laaß, Burkhard Schillinger

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Abstract. Infolded dentine (plicidentine) around the pulp cavities of the tooth roots is an ancient dental feature of fishes (sarcopterygians and actinopterygians) and several basal tetrapod groups. But, plicidentine is completely unknown in synapsids except some sphenacodontid pelycosaurs. An investigation of a skull of Varanosaurus acutirostris (Synapsida, Pelycosauria, Varanopsidae) by means of neutron tomography showed that plicidentine is also present in another group of pelycosaurs and was obviously wider distributed among basal synapsids than previously thought. Furthermore, the presence of plicidentine in this taxon with relatively short tooth roots supports the hypothesis that plicidentine played a functional role in strengthening tooth attachment.

Neutron tomography, Plicidentine, Pelycosauria, Synapsida, Varanosaurus

Published online 1/5/2020, 6 pages
Copyright © 2020 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Michael Laaß, Burkhard Schillinger, The first Record of Plicidentine in Varanopseidae (Synapsida, Pelycosauria), Materials Research Proceedings, Vol. 15, pp 244-249, 2020


The article was published as article 38 of the book Neutron Radiography

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