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Distortodon, new lizard from Cretaceous of Hungary + crocodilian bite force

From: Ben Creisler

A couple of recent non-dino papers of note:

László Makádi (2013)
A new polyglyphanodontine lizard (Squamata: Borioteiioidea) from the
Late Cretaceous Iharkút locality (Santonian, Hungary).
Cretaceous Research 46: 166–176
doi: http://dx.doi.org/10.1016/j.cretres.2013.08.001

In recent years the Late Cretaceous (Santonian) terrestrial vertebrate
locality at Iharkút (western Hungary) has yielded well-preserved
remains of lizard taxa besides the remains of fishes, amphibians,
turtles, crocodiles, pterosaurs and dinosaurs. Previously the
polyglyphanodontine lizard Bicuspidon aff. hatzegiensis has been
reported from Iharkút. However, recent excavations at this site
produced more lacertilian remains including new polyglyphanodontine
material, namely a maxilla and two dentaries which suggest the
presence of a new genus in the Iharkút fauna. This previously unknown
lizard (described here as Distortodon rhomboideus n. g. n. sp.) is
distinct from other polyglyphanodontines such as Bicuspidon,
Paraglyphanodon, Polyglyphanodon, Dicothodon and Peneteius. It differs
from these genera mainly in having the lingual cusp situated more
distally compared to the labial one on its bicuspid teeth located in
the distal part of the tooth row, thus the crowns having a unique
rhomboidal shape in occlusal view. Distortodon rhomboideus further
strengthens the dominance of borioteiioid lizards in the Iharkút
fauna. The growing presence of borioteiioids in European localities
supports previous theories which suggest some paleobiogeographic
connections between the western Tethyan archipelago and North America
in the Late Cretaceous.


G. M. Erickson, P. M. Gignac, A. K. Lappin, K. A. Vliet, J. D.
Brueggen & G. J. W. Webb (2013)
A comparative analysis of ontogenetic bite-force scaling among Crocodylia.
Journal of Zoology (advance online line publication)
DOI: 10.1111/jzo.12081

Interspecific adult bite forces for all extant crocodylian species are
now known. However, how bite forces scale during ontogeny across the
clade has yet to be studied. Here we test the hypotheses that extant
crocodylians share positively allometric and statistically comparable
developmental scaling coefficients for maximal bite-force capacity
relative to body size. To do this, we measured bite forces in the
Australian freshwater crocodile Crocodylus johnsoni and the Saltwater
crocodile C. porosus, and determined how performance changed during
ontogeny. We statistically compared these results with those for the
American alligator Alligator mississippiensis using 95% prediction
intervals and interpreted our findings in a phylogenetic context. We
found no observable taxon-specific shifts in the intraspecific scaling
of biomechanical performance. Instead, all bite-force values in our
crocodylid dataset fell within the bounds of the A. mississippiensis
95% prediction intervals, suggesting similar bite-force capacity when
same-sized individuals are compared. This holds true regardless of
differences in developmental stage, potential adult body size,
rostro-dental form, bone mineralization, cranial suturing, dietary
differences or phylogenetic relatedness. These findings suggest that
intraspecific bite-force scaling for crocodylians with feeding
ecologies comparable with those of extant forms has likely remained
evolutionarily static during their diversification.