Taxonomy and phylogeny of the turtle Tropidemys langii Rütimeyer, 1873, based on new specimens from the Kimmeridgian of the Swiss Jura Mountains

The fossil turtle Tropidemys langii is a representative of Plesiochelyidae, a traditionally recognized group of Late Jurassic turtles diagnosed by the presence of three cervical scutes and adapted to life in the sea. Tropidemys langii was previously only known from fossilized carapaces and, possibly, plastra from Europe, most notably the famous ‘Solothurn Turtle Limestone’ of Switzerland. Due to the sparse fossil record of Tropidemys langii, several questions concerning its taxonomy and phylogeny have remained unanswered. Here, new material of Tropidemys langii is reported from the Kimmeridgian of Porrentruy, Canton Jura, Switzerland. In addition to three well-preserved carapaces, associated plastra and limb bones (humerus and femur) are described for the first time. The type specimens of ‘Tropidemys valanginiensis’ and ‘Pelobatochelys blakii’ lack diagnostic characters, but can nevertheless be referred to Tropidemys. A potential extension of the lineage into the Early Cretaceous is uncertain, however, because the type locality of ‘Tropidemys valanginiensis’ is dubious. A cladistic analysis shows that Tropidemys langii is sister to Plesiochelys solodurensis, thereby tentatively confirming for the first time the monophyly of Plesiochelyidae using cladistic arguments

New occurrences of the wood Protocupressinoxylon purbeckensis francis : implications for terrestrial biomes in southwestern Europe at the jurassic/cretaceous boundary

International audiencePreviously known from the Kimmeridgian-Portlandian of Dorset (UK) only, Protocupressinoxylon purbeckensis wood is reported here from the Kimmeridgian of Asturias (Spain) and Ajoie (Switzerland). The morphospecies taxonomy and nomenclature are discussed, and new supplementary illustrations are given. The P. purbeckensis tree was growing in dry strongly seasonal (tropophilous) environments, and the new occurrences suggest that such a climate prevailed on land all over southwestern Europe at the end of the Jurassic (Kimmeridgian sensu anglico - Portlandian). The review of fossil wood data indicates that such a stressful environment may have constrained terrestrial biocoenoses and their evolution at the Jurassic/Cretaceous boundary. But wood generic diversity curves are also strikingly similar to that drawn 20 years ago for nonmarine tetrapods, implying a fossil Lagerstatte effect

Taxonomy and phylogeny of the turtle <i>Tropidemys langii</i> Rütimeyer, 1873, based on new specimens from the Kimmeridgian of the Swiss Jura Mountains

<div><p>ABSTRACT</p><p>The fossil turtle <i>Tropidemys langii</i> is a representative of Plesiochelyidae, a traditionally recognized group of Late Jurassic turtles diagnosed by the presence of three cervical scutes and adapted to life in the sea. <i>Tropidemys langii</i> was previously only known from fossilized carapaces and, possibly, plastra from Europe, most notably the famous ‘Solothurn Turtle Limestone’ of Switzerland. Due to the sparse fossil record of <i>Tropidemys langii</i>, several questions concerning its taxonomy and phylogeny have remained unanswered. Here, new material of <i>Tropidemys langii</i> is reported from the Kimmeridgian of Porrentruy, Canton Jura, Switzerland. In addition to three well-preserved carapaces, associated plastra and limb bones (humerus and femur) are described for the first time. The type specimens of ‘<i>Tropidemys valanginiensis</i>’ and ‘<i>Pelobatochelys blakii</i>’ lack diagnostic characters, but can nevertheless be referred to <i>Tropidemys</i>. A potential extension of the lineage into the Early Cretaceous is uncertain, however, because the type locality of ‘<i>Tropidemys valanginiensis</i>’ is dubious. A cladistic analysis shows that <i>Tropidemys langii</i> is sister to <i>Plesiochelys solodurensis</i>, thereby tentatively confirming for the first time the monophyly of Plesiochelyidae using cladistic arguments.</p> <p>SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at <a href="http://www.tandfonline.com/UJVP" target="_blank">www.tandfonline.com/UJVP</a></p> </div

Cynocephalid dermopterans from the Palaeogene of South Asia (Thailand, Myanmar and Pakistan) : systematic, evolutionary and palaeobiogeographic implications

International audienc