The University of Southampton
University of Southampton Institutional Repository

Osteology and relationships of Colymbosaurus Seeley, 1874, based on new material of C. svalbardensis from the Slottsmøya Member, Agardhfjellet Formation of central Spitsbergen

Osteology and relationships of Colymbosaurus Seeley, 1874, based on new material of C. svalbardensis from the Slottsmøya Member, Agardhfjellet Formation of central Spitsbergen
Osteology and relationships of Colymbosaurus Seeley, 1874, based on new material of C. svalbardensis from the Slottsmøya Member, Agardhfjellet Formation of central Spitsbergen
Colymbosaurus is a genus of long-necked plesiosaurian represented by two valid species: C. megadeirus from the Upper Kimmeridge Clay Formation (Kimmeridgian–Tithonian) of the United Kingdom and C. svalbardensis from the Slottsmøya Member of the Agardhfjellet Formation (Tithonian–Berriasian) of Svalbard, Norway. Due to the lack of complete and articulated skeletons and a near absence of cranial material, Colymbosaurus has been problematic to characterize morphologically. Here, we describe and conduct a phylogenetic analysis on an informative new specimen referable to C. svalbardensis from the Slottsmøya Member, preserving a large portion of the axial and appendicular skeleton. The new material contributes important new osteological data for the species and together with an extensive examination of congeners in British museums, clarifies the diagnostic characters of the genus. We provide two new diagnostic characters of the epipodials for the genus and reevaluate the utility of an anteroposteriorly oriented bisecting ridge on the distal end of the propodials. We also present two new diagnostic features for C. svalbardensis regarding the neural canal and femoral morphology. A phylogenetic analysis recovers a monophyletic and well-supported Colymbosaurus. The new specimen of C. svalbardensis confirms that this species is not synonymous with other described Slottsmøya Member plesiosauroids, demonstrating considerable diversity of the clade at high latitudes close to the Jurassic–Cretaceous boundary.
0272-4634
Roberts, Aubrey, Jane
a0b4dc95-32c7-4417-8515-e24b0767c3b2
Druckenmiller, Patrick S.
14fd30f0-14b4-4d7f-b65e-e523e1cdec67
Delsett, Lene L.
c8fc3ac5-3e01-4fd1-a7bc-451f6bff612c
Hurum, Jørn H.
417bc987-7ec4-43e4-bf30-1b55dd6a955c
Roberts, Aubrey, Jane
a0b4dc95-32c7-4417-8515-e24b0767c3b2
Druckenmiller, Patrick S.
14fd30f0-14b4-4d7f-b65e-e523e1cdec67
Delsett, Lene L.
c8fc3ac5-3e01-4fd1-a7bc-451f6bff612c
Hurum, Jørn H.
417bc987-7ec4-43e4-bf30-1b55dd6a955c

Roberts, Aubrey, Jane, Druckenmiller, Patrick S., Delsett, Lene L. and Hurum, Jørn H. (2017) Osteology and relationships of Colymbosaurus Seeley, 1874, based on new material of C. svalbardensis from the Slottsmøya Member, Agardhfjellet Formation of central Spitsbergen. Journal of Vertebrate Paleontology, 37 (1), [e1278381]. (doi:10.1080/02724634.2017.1278381).

Record type: Article

Abstract

Colymbosaurus is a genus of long-necked plesiosaurian represented by two valid species: C. megadeirus from the Upper Kimmeridge Clay Formation (Kimmeridgian–Tithonian) of the United Kingdom and C. svalbardensis from the Slottsmøya Member of the Agardhfjellet Formation (Tithonian–Berriasian) of Svalbard, Norway. Due to the lack of complete and articulated skeletons and a near absence of cranial material, Colymbosaurus has been problematic to characterize morphologically. Here, we describe and conduct a phylogenetic analysis on an informative new specimen referable to C. svalbardensis from the Slottsmøya Member, preserving a large portion of the axial and appendicular skeleton. The new material contributes important new osteological data for the species and together with an extensive examination of congeners in British museums, clarifies the diagnostic characters of the genus. We provide two new diagnostic characters of the epipodials for the genus and reevaluate the utility of an anteroposteriorly oriented bisecting ridge on the distal end of the propodials. We also present two new diagnostic features for C. svalbardensis regarding the neural canal and femoral morphology. A phylogenetic analysis recovers a monophyletic and well-supported Colymbosaurus. The new specimen of C. svalbardensis confirms that this species is not synonymous with other described Slottsmøya Member plesiosauroids, demonstrating considerable diversity of the clade at high latitudes close to the Jurassic–Cretaceous boundary.

Text
Osteology and relationships of Colymbosaurus Seeley 1874 based on new material of C svalbardensis from the Slottsm ya Member Agardhfjellet Formation - Version of Record
Download (8MB)

More information

Accepted/In Press date: 31 October 2016
e-pub ahead of print date: 8 March 2017
Organisations: Ocean and Earth Science, Paleooceanography & Palaeoclimate

Identifiers

Local EPrints ID: 408035
URI: http://eprints.soton.ac.uk/id/eprint/408035
ISSN: 0272-4634
PURE UUID: 72dccd83-f743-4ba7-8c62-946a75f4fbe5

Catalogue record

Date deposited: 10 May 2017 01:04
Last modified: 08 Jan 2022 13:11

Export record

Altmetrics

Contributors

Author: Aubrey, Jane Roberts
Author: Patrick S. Druckenmiller
Author: Lene L. Delsett
Author: Jørn H. Hurum

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×