Taxonomic utility of Early Cretaceous Australian plesiosaurian vertebrae
نویسندگان
چکیده
Despite their broad occurrence in Australian basins, lower-level taxonomy of Early Cretaceous plesiosaurs is hindered by the scarcity skulls and other diagnostic elements. This paper presents a morphological morphometric analysis vertebrae comparison with selected non-Australian elasmosaurids (basal elasmosaurs, styxosaurines, aristonectines). Biometric involved measurements that include centrum height (CH), width (CW), length (CL), zygapophyses, others. Principal component (PCA) multivariate variance (MANOVA) were carried out on CH, CW, CL. Morphometric ratios [Vertebral Length Index (VLI), Height (HI), Breadth (BI)] plotted along vertebral column bivariate graphs where independent position correct sequencing. Direct homologous groups (especially anterior cervicals) easily distinguished an polycotylid from all plots. Most elasmosaurid specimens near basal ‘Cimoliasaurus’- grade they clustered as group relatively distinct from, but overlapping coeval forms. However, one specimen consistently styxosaurines Opallionectes andamookaensis aristonectines. Although it not possible to distinguish phylogenetic relationships convergence positions, analyses provide potential hypotheses be tested additional data. Hence, have some taxonomic value for assignment plesiosaurs, even absence or material.
منابع مشابه
Reappraisal of Europe’s most complete Early Cretaceous plesiosaurian: Brancasaurus brancai Wegner, 1914 from the “Wealden facies” of Germany
The holotype of Brancasaurus brancai is one of the most historically famous and anatomically complete Early Cretaceous plesiosaurian fossils. It derived from the Gerdemann & Co. brickworks clay pit near Gronau (Westfalen) in North Rhine-Westphalia, northwestern Germany. Stratigraphically this locality formed part of the classic European "Wealden facies," but is now more formally attributed to t...
متن کاملLumbosacral Transitional Vertebrae and Its Prevalence in the Australian Population
Study Design Retrospective cohort study. Objective Lumbosacral transitional vertebrae (LSTV) are a common congenital anomaly, and they can be accurately identified on anteroposterior (AP) radiographs of the lumbosacral spine. This study attempts to determine the prevalence of this congenital anomaly and to increase awareness among all clinicians to reduce the risk of surgical and procedural err...
متن کاملTaxonomic Composition and Trophic Structure of the Continental Bony Fish Assemblage from the Early Late Cretaceous of Southeastern Morocco
The mid-Cretaceous vertebrate assemblage from south-eastern Morocco is one of the most diversified continental vertebrate assemblages of this time worldwide. The bony fish component (coelacanths, lungfishes and ray-finned fishes) is represented by relatively complete specimens and, mostly, by fragmentary elements scattered along 250 kilometres of outcrops. Here we revisit the bony fish assembla...
متن کاملNew Australian sauropods shed light on Cretaceous dinosaur palaeobiogeography
Australian dinosaurs have played a rare but controversial role in the debate surrounding the effect of Gondwanan break-up on Cretaceous dinosaur distribution. Major spatiotemporal gaps in the Gondwanan Cretaceous fossil record, coupled with taxon incompleteness, have hindered research on this effect, especially in Australia. Here we report on two new sauropod specimens from the early Late Creta...
متن کاملA taxonomic revision of Australian Conopidae (Insecta: Diptera)
A taxonomic revision of the Australian Conopidae is presented. Nineteen genera in four subfamilies are recognised. The Stylogasterinae are represented by the cosmopolitan genus Stylogaster Macquart and the Myopinae by Myopa Fabricius and Thecophora Rondani. A monotypic genus, Notoconops gen. nov., is described and placed in a new subfamily, Notoconopinae. The remaining fifteen Australian genera...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Palaeontologia Electronica
سال: 2021
ISSN: ['1094-8074', '1532-3056', '1935-3952']
DOI: https://doi.org/10.26879/1095