BioOne.org will be down briefly for maintenance on 17 December 2024 between 18:00-22:00 Pacific Time US. We apologize for any inconvenience.
How to translate text using browser tools
21 December 2019 A New Specimen of Stenorhynchosaurus munozi Páramo-Fonseca et al., 2016 (Plesiosauria, Pliosauridae), from the Barremian of Colombia: New Morphological Features and Ontogenetic Implications
María E. Páramo-Fonseca, Cristian D. Benavides-Cabra, Ingry E. Gutiérrez
Author Affiliations +
Abstract

A new specimen of Stenorhynchosaurus munoziPáramo-Fonseca et al., 2016 (Plesiosauria, Pliosauridae), found at Sáchica (Boyacá, Colombia) in upper Barremian beds of the Arcillolitas Abigarradas Member of the Paja Formation, is described herein. It consists of a complete skull and 10 cervical vertebrae of an adult individual and provides valuable new morphological information on the species: the presence of nasals covering a subsurface circular cavity where salt glands were probably lodged (new autapomorphy), the presence of a high sagittal crest on the parietal, a very elongated pineal foramen enclosed entirely within the parietals, and unfused neural arches in the cervical vertebrae. A phylogenetic analysis supports the inclusion of Stenorhynchosaurus munozi within the pliosaurid clade Brachaucheninae. A morphological comparison between the juvenile and adult stages of S. munozi shows that in the adult stage, the margins of the internal nares and the anterior part of the anterior interpterygoid vacuity are well ossified, the medial joints of the pterygoids and the mandibular symphysis are closed, and the atlas and the axis are fused, but the cervical neural arches remain unfused to the centra. The growth pattern of the skull dorsal bones differs from that of the palatal elements, but the relative distance between the external and internal nares remains the same. A greater longitudinal growth in the skull and a negative allometric orbital growth pattern results in a proportionally longer skull and relatively smaller orbits in the adult.

© by the Society of Vertebrate Paleontology
María E. Páramo-Fonseca, Cristian D. Benavides-Cabra, and Ingry E. Gutiérrez "A New Specimen of Stenorhynchosaurus munozi Páramo-Fonseca et al., 2016 (Plesiosauria, Pliosauridae), from the Barremian of Colombia: New Morphological Features and Ontogenetic Implications," Journal of Vertebrate Paleontology 39(4), (21 December 2019). https://doi.org/10.1080/02724634.2019.1663426
Received: 5 March 2019; Accepted: 10 July 2019; Published: 21 December 2019
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top