Cynopodius, a long-toothed chondrichthyan from the Carboniferous of Scotland and the USA
Resource type
Journal article
Creator (person)
Date published
October 22, 2025
Abstract
The distinctive isolated elements of , characterised by their deep narrow base and spatulate crown, were first described (as spine-like elements) by Ramsay Heatley Traquair in the late 19th Century, based on specimens from the Burghlee Ironstone (Serpukhovian, Carboniferous) at Loanhead near Edinburgh, Scotland. The type species is also known from older Calciferous Sandstone Measures (Viséan) of Fife. Here we provide evidence that the elements are teeth rather than spines or dermal claspers, as hypothesised elsewhere. Thin sections of the teeth, illustrated for the first time, show osteodentine and tubate dentine forming the crown, covered by a thin outer hypermineralised layer on the cusps, and trabecular osteodentine or acellular bone forming the base. In recent decades, teeth of have also been collected from the lower Carboniferous Sainte Genevieve Formation (Mississippian: Viséan) of Iowa, Kentucky, and West Virginia in the USA. We assign these teeth from Iowa to n. sp. They are distinguished from the type species by their relative robustness, with a ratio of maximum crown length to root length of c. 2:3 for and c. 1:2 for , and lack of longitudinal curvature. The Scottish and American occurrences, though widely separated in the early Carboniferous, are the only known localities for the genus. The similarity between these over 300-million-year-old teeth and those of Recent long-toothed teleost reef fishes like , for instance, suggests that the animals might also have been specialised detritivores.
Journal title
Earth and Environmental Science Transactions of the Royal Society of Edinburgh
Publisher
Cambridge University Press (CUP)
ISSN
1755-6910
eISSN
1755-6929
Official URL
Rights statement
In Copyright