Skip to content Skip to navigation

Article: Postcanine microstructure in Cricodon metabolus, a Middle Triassic gomphodont cynodont from south‐eastern Africa

Palaeontology Cover Image - Volume 59 Part 6
Publication: Palaeontology
Volume: 59
Part: 6
Publication Date: November 2016
Page(s): 851 861
Author(s): Christophe Hendrickx, Fernando Abdala, and Jonah Choiniere
Addition Information

How to Cite

HENDRICKX, C., ABDALA, F., CHOINIERE, J. 2016. Postcanine microstructure in Cricodon metabolus, a Middle Triassic gomphodont cynodont from south‐eastern Africa. Palaeontology, 59, 6, 851-861. DOI: 10.1111/pala.12263

Author Information

  • Christophe Hendrickx - Evolutionary Studies Institute University of the Witwatersrand Johannesburg South Africa (Email: christophendrickx@gmail.com)
  • Fernando Abdala - Evolutionary Studies Institute University of the Witwatersrand Johannesburg South Africa (Email: nestor.abdala@wits.ac.za)
  • Jonah Choiniere - Evolutionary Studies Institute University of the Witwatersrand Johannesburg South Africa (Email: jonah.choiniere@wits.ac.za)

Publication History

  • Manuscript Accepted: 31 August 2016
  • Manuscript Received: 09 March 2016

Funded By

DST‐NRF Centre of Excellence. Grant Number: PPD2015/17
National Research Foundation

Online Version Hosted By

Wiley Online Library
Get Article: Wiley Online Library [Pay-to-View Access] |

Abstract

Cricodon metabolus is a trirachodontid cynodont from the Anisian (Middle Triassic) of eastern and southern Africa. It has labiolingually expanded (gomphodont) postcanines but also a sectorial tooth in the last postcanine locus. In this paper, we examine the crown microstructure of isolated sectorial and gomphodont postcanines belonging to the holotype specimen of this taxon using scanning electron microscopy. The enamel of both teeth is prismless and composed of discontinuous columnar divergence units, supporting the consistent presence of synapsid columnar enamel in cynognathians. Abundant tubules and numerous irregularly spaced incremental lines are also visible in the enamel and dentine layers in each tooth. This study reveals that the enamel thickness varies along the tooth row in Cricodon as the enamel layer of the gomphodont postcanines is 11.5 times thicker than that of the sectorial crown. It is likely that this difference reflects occlusal stresses and fewer replacements in gomphodont postcanines relative to sectorial teeth. Approximately 100 incremental growth lines of von Ebner are present in the dentine layer, indicating that the deposition of the dentine by odontoblasts occurred for three months before the animal's death.

PalAss Go! URL: http://go.palass.org/hsq | Twitter: Share on Twitter | Facebook: Share on Facebook | Google+: Share on Google+