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[dinosaur] New Lariosaurus species from Middle Triassic of Germany + new Ichthyosaurus conybeari specimen

Ben Creisler

Two new marine reptiles papers in the JVP:

Lariosaurus  vosseveldensis

Nicole Klein, Dennis F. A. E. Voeten, Adam Haarhuis & Remco Bleeker (2016)
The earliest record of the genus Lariosaurus from the early middle Anisian (Middle Triassic) of the Germanic Basin. 
Journal of Vertebrate Paleontology (advance online publication) 
DOI: 10.1080/02724634.2016.1163712
http: // www.tandfonline.com/doi/full/10.1080/02724634.2016.1163712

A new skull representing the oldest record of the genus Lariosaurus in the Germanic Basin is described. The small-sized skull originates from the early middle Anisian (Bithynian) of the Winterswijkse Steengroeve (Winterswijk, The Netherlands) and is assigned to L. vosseveldensis, sp. nov. Supplementation of a recently established phylogeny with L. vosseveldensis, sp. nov., recovered it within Lariosaurus as the sister taxon to Nothosaurus winkelhorsti and L. buzzii. The generic assignment of N. juvenilis, N. youngi, and N. winkelhorsti to Nothosaurus must be reevaluated to reestablish support for a monophyletic Lariosaurus, and only a definitive resolution of the polytomy including Germanosaurus could recover a monophyletic Nothosauridae. The Winterswijk locality has previously yielded a rich and diverse marine reptile fauna, including an endemic basal placodont. The nearly contemporaneous occurrence of L. vosseveldensis, sp. nov., and L. hongguoensis from the middle Anisian (Pelsonian) of China indicates a very rapid dispersal of the group, but does not resolve the origin of Sauropterygia (eastern Tethyan faunal province vs. western Tethyan faunal province).



Judy A. Massare & Dean R. Lomax (2016)
A new specimen of Ichthyosaurus conybeari (Reptilia, Ichthyosauria) from Watchet, Somerset, England, U.K., and a reexamination of the species. 
Journal of Vertebrate Paleontology (advance online publication) 
DOI: 10.1080/02724634.2016.1163264.
http: // www.tandfonline.com/doi/full/10.1080/02724634.2016.1163264

Ichthyosaurus conybeari is a rare species, previously known only from an incomplete holotype and one referred specimen, both from the Lyme Regis area of the west Dorset coast, U. K. A newly recognized, nearly complete specimen (NMW 93.5G.2) is the first occurrence of the species in Somerset, U. K. A revised diagnosis recognizes new morphological characters that distinguish the species: slender maxilla with a long, delicate premaxillary process; narrow postorbital; humerus with an anteriorly offset dorsal process that has a well-defined lip extending slightly into the shaft; fibula that is much larger dorsoventrally and mediodistally than tibia; and wide rectangular ischium that is much shorter than the pubis and femur. Notching of anterior fin elements in the forefin had been used as a diagnostic character, but a review of notching within Ichthyosaurus suggests that it has little taxonomic utility. Another specimen (NHMUK R15907), herein referred to the species, extends the range of I. conybeari from the upper Hettangian to lower Pliensbachian stages of the Lower Jurassic, the longest duration of any species of the genus.

SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP