Micro-computed tomography imaging reveals the development of a unique tooth mineralization pattern in mackerel sharks (Chondrichthyes; Lamniformes) in deep time

Autor(en)

Patrick Leopold Jambura, R. Kindlimann, Giuseppe Marrama, Cathrin Pfaff, Sebastian Stumpf, Julia Türtscher, Charlie J. Underwood, D.J. Ward, Jürgen Kriwet

Abstrakt

The cartilaginous fishes (Chondrichthyes) have a rich fossil record which consists mostly of isolated teeth and, therefore, phylogenetic relationships of extinct taxa are mainly resolved based on dental characters. One character, the tooth histology, has been examined since the 19

^th century, but its implications on the phylogeny of Chondrichthyes is still in debate. We used high resolution micro-CT images and tooth sections of 11 recent and seven extinct lamniform sharks to examine the tooth mineralization processes in this group. Our data showed similarities between lamniform sharks and other taxa (a dentinal core of osteodentine instead of a hollow pulp cavity), but also one feature that has not been known from any other elasmobranch fish: the absence of orthodentine. Our results suggest that this character resembles a synapomorphic condition for lamniform sharks, with the basking shark, Cetorhinus maximus, representing the only exception and reverted to the plesiomorphic tooth histotype. Additionally, †Palaeocarcharias stromeri, whose affiliation still is debated, shares the same tooth histology only known from lamniform sharks. This suggests that †Palaeocarcharias stromeri is member of the order Lamniformes, contradicting recent interpretations and thus, dating the origin of this group back at least into the Middle Jurassic.

Organisation(en)

Institut für Paläontologie

Externe Organisation(en)

Haimuseum und Sammlung R. Kindlimann, University of London, Natural History Museum London

Journal

Scientific Reports

Band

9

Seiten

1-13

Anzahl der Seiten

13

ISSN

2045-2322

DOI

https://doi.org/10.1038/s41598-019-46081-3

Publikationsdatum

2019

Peer-reviewed

Ja

ÖFOS 2012

106012 Evolutionsforschung, 106010 Entwicklungsbiologie, 105118 Paläontologie

Schlagwörter

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/085275be-c601-4cdb-acda-b7e40debcf47