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

ABSTRACT: 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 resu

SUBMITTER: Jambura PL 

PROVIDER: S-EPMC6609643 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature