The dentition of the narrownose smoothhound shark Mustelus schmitti

BELLEGGIA MAURO; FIGUEROA DANIEL E.; BREMEC CLAUDIA

MARINE AND FRESHWATER RESEARCH

CSIRO PUBLISHING

Lugar: Collingwood ; Año: 2014 vol. 65 p. 688 - 696

1323-1650

This study provides a quantitative and qualitative analysis on the dentition of Mustelus schmitti, and estimates the tooth replacement rate. A total of 47 males and 56 females of M. schmitti were collected on scientific trawl surveys conducted by the The National Institute of Fisheries Research and Development (INIDEP) in Argentina during the months of November 2007, November 2008, and December 2008. The dental laminas were extracted from the jaw cartilage and attached to onionskin paper for dehydration treatment, maintaining their original jaw position. Tooth replacement rate was estimated following established methods used for fossil sharks, instead of the established technique of clipping teeth, based on the premise that tooth length within each row decreases from the lingual to the labial side of the jaw as a consequence of wear. The length difference between consecutive teeth in four representative rows should be proportional to the tooth replacement rate. Mustelus schmitti exhibited homodont dentition, where teeth were similar in shape or design, and are arranged in a semi-pavement like dentition. The dental formula was 47-63 / 50-63 for juveniles and 50-77 / 50-69 for adult specimens. The estimated mean replacement rate was 4 days series-1.