[dinosaur] Garjainia (Triassic erythrosuchid) cranial anatomy = "Vjushkovia" jun. synonym (free pdf)

Ben Creisler
[email protected]

A new paper in open access:

Richard J. Butler, Andrey G. Sennikov, Emma M. Dunne, Martin D. Ezcurra,
Brandon P. Hedrick, Susannah C. R. Maidment, Luke E. Meade, Thomas J. Raven
and David J. Gower (2019)
Cranial anatomy and taxonomy of the erythrosuchid archosauriform
'Vjushkovia triplicostata' Huene, 1960, from the Early Triassic of European
Russia.
Royal Society Open Science 6(11):
doi: https://urldefense.proofpoint.com/v2/url?u=https-3A__doi.org_10.1098_rsos.191289&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=A3eRjb0Qb-f9WJVFzNO8yMU2tQVZJH7g7v1VDpqGS6E&s=qCdjPzCq7upYptgsEMphJxxWIGV82XIw8BRj3chnJkM&e= 
https://urldefense.proofpoint.com/v2/url?u=https-3A__royalsocietypublishing.org_doi_10.1098_rsos.191289&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=A3eRjb0Qb-f9WJVFzNO8yMU2tQVZJH7g7v1VDpqGS6E&s=Z2NuuWmJ6swceMGsjD4OXESV6meXPFpzArOF_kjlLo0&e= 
Free pdf:
https://urldefense.proofpoint.com/v2/url?u=https-3A__royalsocietypublishing.org_doi_pdf_10.1098_rsos.191289&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=A3eRjb0Qb-f9WJVFzNO8yMU2tQVZJH7g7v1VDpqGS6E&s=-qkwPPWdwMm7ZFYbkJn8z_4U51uKpdaIFvHtD_npPG4&e= 


Erythrosuchidae are a globally distributed and important group of apex
predators that occupied Early and Middle Triassic terrestrial ecosystems
following the Permo-Triassic mass extinction. The stratigraphically oldest
known genus of Erythrosuchidae is Garjainia Ochev, 1958, which is known
from the late Early Triassic (late Olenekian) of European Russia and South
Africa. Two species of Garjainia have been reported from Russia: the type
species, Garjainia prima Ochev, 1958, and 'Vjushkovia triplicostata' von
Huene, 1960, which has been referred to Garjainia as either congeneric
(Garjainia triplicostata) or conspecific (G. prima). The holotype of G.
prima has received relatively extensive study, but little work has been
conducted on type or referred material attributed to ‘V. triplicostata’.
However, this material includes well-preserved fossils representing all
parts of the skeleton and comprises seven individuals. Here, we provide a
comprehensive description and review of the cranial anatomy of material
attributed to 'V. triplicostata', and draw comparisons with G. prima. We
conclude that the two Russian taxa are indeed conspecific, and that minor
differences between them result from a combination of preservation or
intraspecific variation. Our reassessment therefore provides additional
information on the cranial anatomy of G. prima. Moreover, we quantify
relative head size in erythrosuchids and other early archosauromorphs in an
explicit phylogenetic context for the first time. Our results show that
erythrosuchids do indeed appear to have disproportionately large skulls,
but that this is also true for other early archosauriforms (i.e.
proterosuchids), and may reflect the invasion of hypercarnivorous niches by
these groups following the Permo-Triassic extinction.