Vladlenosaurus

Vladlenosaurus Temporal range: Early Triassic
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Amphibia
Order:	Temnospondyli
Suborder:	Stereospondyli
(unranked):	Capitosauria
Genus:	Vladlenosaurus Morkovin and Novikov, 2000
Species
V. alexeyevi Morkovin and Novikov, 2000 (type)

Vladlenosaurus is an extinct genus of capitosaur from Russia. It lived during the late Vetlugian (Early Triassic). Based on the type of deposits it was found in, Vladlenosaurus probably inhabited lacustrine, or lake, habitats. The type species is V. alexeyevi, named in 2000.

Description

Unlike the flatter, more rounded snouts of other capitosaurs, Vladlenosaurus had a wedge-shaped snout. This characteristic is also seen in trematosaurians, although it was independently acquired in both cases as a result of convergent evolution.^[1]

Classification

Vladlenosaurus is similar in appearance to the benthosuchids, a group of trematosauroid temnospondyls, but is more closely related to mastodonsauroids. Among capitosaurs, it shares many features with the basal form Wetlugasaurus, also from the Early Triassic of Russia. Vladlenosaurus alexeyevi was even considered to be a species of Wetlugasaurus in a 2006 study.^[2] In a 2011 phylogenetic analysis, the first to incorporate Vladlenosaurus, the genus was found to be most closely related to Odenwaldia.^[1] It and Odenwaldia formed a basal clade of capitosaurs more derived than Wetlugasaurus, the most basal capitosaur. Below is a modified cladogram from Fortuny et al (in press) showing the relationship of Vladlenosaurus to other stereospondyls:^[1]

Stereospondyli	Lydekkerina Rhinesuchidae  Capitosauria  Wetlugasaurus Odenwaldia Vladlenosaurus Edingerella Watsonisuchus Xenotosuchus Cherninia Paracyclotosaurus Stenotosauridae Heylerosauridae Mastodonsauridae Trematosauria

References

1. Fortuny, Josep; Galobart, À; De Santisteban, C. (2011). "A new capitosaur from the Middle Triassic of Spain and the relationships within the Capitosauria" (PDF). Acta Palaeontologica Polonica. 56 (in press). doi:10.4202/app.2010.0025.
2. Shishkin, M.A.; Sennikov, A.G; Novikov, I.V.; Ilyina, N.V. (2006). "Differentiation of tetrapod communities and some aspects of biotic events in the early triassic of Eastern Europe". Paleontological Journal. 40 (1): 1–10. doi:10.1134/S0031030106010011.