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Review of Russian Upper Jurassic ichthyosaurs--Grendelius valid (free pdf)

Ben Creisler

A new paper:

N. G. Zverkov, M. S. Arkhangelsky and  I. M. Stenshin (2015)
A review of Russian Upper Jurassic ichthyosaurs with an
intermedium/humeral contact. Reassessing Grendelius McGowan, 1976.
Proceedings of the Zoological Institute 318(4): 558-588




The Upper Jurassic ichthyosaurs, characterized by the
intermedium/humeral contact are known from several localities in
Europe and North America. However, they are often described either
briefly, or based on fragmentary material, resulting in a taxonomic
tangle in most overviews. Grendelius McGowan, 1976 was previously
synonymized with Brachypterygius Huene, 1922. However, it possesses a
number of distinct features: intermedium with wide distally faced
facet for distal carpal 3 (faced anterodistally in Brachypterygius and
equal in size with distal carpal 4 facet), posterodistal contact of
metacarpal 5 with ulnare (distal in Brachypterygius), and absence of
postaxial accessory digit (well developed in Brachypterygius). We
apply a cladistic analysis to place Grendelius and Brachypterygius in
a phylogenetic context. Our analysis recovered Brachypterygius and
Grendelius as distinct groups. The clade Grendelius + Otschevia gives
us good reason to regard the genus Otschevia Efimov, 1998 as a
subjective junior synonym of Grendelius.


Thanks to Vahe Demirjian for the heads-up. This paper is not yet
posted on the English language version of the journal.