Research paper

Characterization of coelacanth scales from the Early Cretaceous freshwater locality of Las Hoyas, upper Barremian (Cuenca, Spain)


HUGO MARTÍN-ABAD
JURASSICA Museum, Route de Fontenais 21, 2900 Porrentruy, Switzerland. hugo.martin.abad@gmail.com

Department of Geosciences, University of Fribourg, Chemin du Musée 6, 1700 Fribourg, Switzerland.

Unidad de Paleontología, Departamento de Biología, Universidad Autónoma de Madrid, Calle Darwin 2, 28049 Madrid, Spain.
Corresponding author

MICHAEL G. NEWBREY
Department of Biology, Columbus State University, Columbus, Georgia 31907, USA. newbrey_michael@columbusstate.edu

Canadian Fossil Discovery Centre, 111 Gilmour Street, Morden, Manitoba R6M 1N9, Canada.

FRANCES WOOLFOL
Department of Biology, Columbus State University, Columbus, Georgia 31907, USA. woolfolk_frances@columbusstate.edu

CANDELA BLANCO-MORENO
Unidad de Paleontología, Departamento de Biología, Universidad Autónoma de Madrid, Calle Darwin 2, 28049 Madrid, Spain. candela.blanco@uam.es


ABSTRACT

Coelacanths are rare, mostly marine fishes, but the species from the Lower Cretaceous Spanish locality of Las Hoyas (Barremian) is a freshwater form and we know almost nothing about it. The Las Hoyas specimens are very rare and relatively incomplete, but there are still many things we can learn from the isolated skeletons and scales. First, the coelacanth scales were distinguished from other superficially similar scales (i.e., other “amioid” scales). Coelacanth scales are distinguished by the presence of a smooth central surface, a particular pattern of arrangement of concentric growth cessation marks, and mainly a relatively short posterior fi eld with thick elongated ridges. Only a few articulated coelacanth specimens have been recovered from Las Hoyas to date, and only 7.3% (n = 11) of the total isolated scales are coelacanth. The Las Hoyas coelacanth scales represent relatively large individuals. This suggests that a natural population of the coelacanth may have not inhabited permanently the freshwater pool represented by the excavated area of Las Hoyas because small juveniles should be the most common sizes.


Key words: Isolated scales, scale anatomical characters, coelacanth palaeobiology, Latimeriidae.

How to cite: Martín-Abad, H., Newbrey, M.G., Woolfolk, F. & Blanco-Moreno, C. 2017. Characterization of coelacanth scales from the Early Cretaceous freshwater locality of Las Hoyas, upper Barremian (Cuenca, Spain). Spanish Journal of Palaeontology, 32 (2), 331-342.

Received 9 December 2016, Accepted 22 May 2017, Published 31 December 2017

https://doi.org/10.7203/sjp.32.2.17047