Vegasaurus molyi , gen. et sp. nov. (Plesiosauria, Elasmosauridae), from the Cape Lamb Member (lower Maastrichtian) of the Snow Hill Island Formation, Vega Island, Antarctica, and remarks on Wedellian Elasmosauridae

• Main Authors: O’Gorman, José P., Salgado, Leonardo, Olivero, Eduardo B., Marenssi, Sergio A.
• Format: Dataset
• Language: unknown
• Published: Taylor & Francis 2015
• Subjects: Inorganic Chemistry; FOS Chemical sciences; Developmental Biology; Biological Sciences; Ecology; FOS Biological sciences; Earth and Environmental Sciences; Evolutionary Biology; Physiology; Antarctic; Cape Lamb; Hill Island; Ross Archipelago; Snow Hill; Snow Hill Island; Vega Island; Antarc*; Antarctica
• Online Access: https://dx.doi.org/10.6084/m9.figshare.1422121.v1; https://tandf.figshare.com/articles/dataset/_i_Vegasaurus_molyi_i_gen_et_sp_nov_Plesiosauria_Elasmosauridae_from_the_Cape_Lamb_Member_lower_Maastrichtian_of_the_Snow_Hill_Island_Formation_Vega_Island_Antarctica_and_remarks_on_Wedellian_Elasmosauridae/1422121/1

ABSTRACT—A new elasmosaurid, Vegasaurus molyi , gen. et sp. nov., from Vega Island, James Ross Archipelago, Antarctica, is described. The holotype and only specimen of this species (MLP 93-I-5-1) was collected from the lower Maastrichtian Cape Lamb Member of the Snow Hill Island Formation. Vegasaurus molyi is the only Antarctic elasmosaurid and one of only a few Late Cretaceous elasmosaurids from the Southern Hemisphere whose postcranial anatomy is well known. Vegasaurus molyi is distinguished from other elasmosaurids by the following combination of characters: cervical region with 54 vertebrae with elongated centra, dumbbell-shaped articular faces and lateral ridge present in the anterior and middle parts of the neck but absent in the posterior-most cervical vertebrae; scapula with ventral ramus bearing a strong ridge in the anteromedial corner of its dorsal surface; ilium shaft with expanded distal end, divided into two parts forming an angle of 140° opening anteriorly; and humerus with anterior knee and prominent posterior projection with accessory posterior articular facet. Preliminary phylogenetic analysis places V. molyi within a clade that includes the Late Cretaceous Wedellian aristonectine elasmosaurids, Aristonectes and Kaiwhekea . This indicates a close relationship between Aristonectinae and non-Aristonectinae Late Cretaceous Weddellian elasmosaurids and suggests a Weddellian origin for the Aristonectinae.http://zoobank.org/urn:lsid:zoobank.org:pub:1B9D10DA-0373-41B5-BFFF-E7AC25D79BF3SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP