A new Barremian (Early Cretaceous) ichthyosaur from western Russia

Simbirskiasaurus and Pervushovisaurus reassessed: implications for the taxonomy and cranial osteology of Cretaceous platypterygiine ichthyosaurs

“…This condition is seen in many platypterygiines, including Platypterygius hercynicus and Sveltonectes insolitus (Fischer et al, 2011b;Fischer, 2012, respectively), but contrasts with the situation present in ophthalmosaurines (Ophthalmosaurus spp., see Gilmore, 1905;Kirton, 1983;and Leninia stellans Fischer et al, 2014a). Ochev and Efimov, 1985, holotype (YKM 65119) …”

“…Simbirskiasaurus birjukovi is also characterized by the following unique combination of features: subnarial process of the premaxilla reaches the posterior margin of the external naris (shared with Cryopterygius kristiansenae Druckenmiller et al, 2012); elongated anterior process of the maxilla, reaching anteriorly the level of the nasal [unlike in Aegirosaurus leptospondylus Bardet & Fernandez, 2000 and Sveltonectes insolitus (Fischer et al, 2011b)]; presence of a supranarial process of the premaxilla [shared with Platypterygius australis (McCoy, 1867), see Kear, 2005, and possibly Pervushovisaurus bannovkensis (Arkhangelsky, 1998b)]. …”

“…Fernández & Talevi, 2014) and the Cretaceous (e.g. Bardet, 1994;Fischer et al, 2011a); however, the taxonomie diversity of Cretaceous ichthyosaurs has recently increased, with the recognition of several new taxa in the Albian of North America (Maxwell & Caldwell, 2006b, 2006aDruckenmiller & Maxwell, 2010;Maxwell & Druckenmiller, 2011) and the Early Cretaceous of Eurasia and the Middle East (Fischer et al, 2011b(Fischer et al, , 2013(Fischer et al, , 2014a. Our knowledge of Cretaceous ichthyosaur diversity is still poor (Zammit, 2012), however, especially outside the better-known intervals of the latest Jurassic-earliest Cretaceous ('Volgian'; e.g.…”

Morphology and orientation of the ichthyosaurian femur

“…The articular condyle appears prominent and convex ventrally, unlike many ophthalmosaurids (Ophthalmosaurus icenicus, Sveltonectes insolitus, Acamptonectes densus, and Platypterygius australis), where the condyle is divided by a wide groove (Kirton 1983;Kear 2005;Fischer et al 2011Fischer et al , 2012. The fossa surangularis is present on the surangular bone and appears well developed unlike in Sveltonectes insolitus (Fischer et al 2011).…”

“…Most of the ophthalmosaurids have three distal facets: Ophthalmosaurus icenicus (Kirton 1983), Aegirosaurus leptospondylus (Bardet and Fernandez 2000), Caypullisaurus bonapartei (Fernandez 1997), Brachy pterygius extremus (Boulenger 1904), Undorosaurus goro dischensis (Efimov 1999), Janusaurus lundi (Roberts et al 2014), Acamptonectes densus (Fischer et al 2012), and Arthropterygius (Maxwell 2010). The ophthalmosaurids with only two distal facets are Cryopterygius kristiansenae (three distal facets on the right humerus; , Nannopterygius enthekiodon (Hulke 1871), Sveltonectes (Fischer et al 2011), and many species of Platypterygius (McGowan and Motani 2003). The forefin of Platypterygius americanus from the Lower Cretaceous is similar to C. kielanae (Maxwell and Kear 2010).…”