It is generally assumed that the Neogene crocodylian fauna of Europe has been represented only by brevirostrine alligatoroid Diplocynodon and longirostrine false gharials (Gavialosuchus and/or Tomistoma), which became extinct prior to 6 Mya. Thus, phylogenetic problems remain with respect to longirostrine clade, and more attention should be paid to resolving their evolutionary relationships amongst the crocodyliforms. If Thalattosuchia is excluded, both Goniopholididae and Pholidosauridae become paraphyletic assemblages. Goniopholididae is a non-monophyletic group however, if dyrosaurids are not included in the analysis, the result differs and the goniopholidids form a distinct clade. A phylogenetic analysis, using 47 taxa and 234 morphological characters, shows the dyrosaurids as the sister taxon of pholidosaurids, which include Elosuchus, Sarcosuchus, Terminonaris and Pholidosaurus, and the thalattosuchians. phosphaticus, present in contemporaneous levels of Algeria and Tunisia, by several autapomorpies, including a smooth dorsal margin of the parietal and widely opened choanae. nov., is currently only known from Morocco. This new Dyrosaurus species, Dyrosaurus maghribensis sp. It is based on numerous cranial and postcranial remains, allowing an almost complete reconstruction. We discuss additional benefits of barcoding to ecology and conservation.Ī new dyrosaurid is described from the Ypresian of the phosphatic deposits of the Oulad Abdoun Basin of Morocco. DNA barcoding offers promise as an effective tool for monitoring poaching and commercial trade in endangered species, especially when investigating semi-processed or morphologically indistinguishable wildlife products. Barcode sequences also differentiated among newly identified lineages of African crocodiles and identified unusually high levels of genetic diversity in one species of African duiker. Both fixed character differences and tree-based maximum likelihood distance methods unambiguously identified unknown and misidentified samples with a high degree of certainty. Polymorphism in the COX1 fragment was generally low (mean = 0.24%), while differences between congeneric species averaged 9.77%. For most taxa, we sequenced multiple individuals to estimate intraspecific sequence variability and document fixed diagnostic characters for species identification. Primer cocktails yielded high quality barcode sequences for 179 out of 204 samples (87.7%) from all species included in the study. We used universal primers to generate reference barcode sequences of 645 bp for 23 species from five vertebrate families (Crocodilidae, Alligatoridae, Bovidae, Suidae and Cercopithecidae). Here, we contribute to the Barcode of Life Data System and test whether a short region of the mitochondrial cytochrome c oxidase subunit 1 (COX1) gene would reliably distinguish among a suite of commonly hunted African and South American mammal and reptile species. The creation and use of a globally available database of DNA sequences from a standardized gene region has been proposed as a tool for species identification, assessing genetic diversity and monitoring the legal and illegal trade in wildlife species.
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