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Youngest record of metriorhynchid crocodylomorph from Lower Cretaceous
A new paper:
Alfio A. Chiarenza, Davide Foffa, Mark T. Young, Gianni Insacco,
Andrea Cau, Giorgio Carnevale & Rita Catanzariti (2015)
The youngest record of metriorhynchid crocodylomorphs, with
implications for the extinction of Thalattosuchia.
Cretaceous Research 56: 608–616
A tooth of a metriorhynchid crocodylomorph from the Aptian of Sicily
This specimen represents the most recent evidence of metriorhynchid
Such evidence falsifies Thalattosuchia extinction early in the Early Cretaceous.
Here we describe an isolated tooth of a metriorhynchid crocodylomorph
from the Hybla Formation (Aptian, Lower Cretaceous) of Rocca Chi Parra
quarry (Montagna Grande, Calatafimi, Trapani Province), Sicily, Italy.
The specimen shares with the Upper Jurassic taxon Plesiosuchus
manselii a mediolaterally compressed conical tooth crown, noticeable
lingual curvature, mesial and distal carinae with microscopic,
rectangular contiguous denticles, strong distal curvature of the
mesial margin, and the presence of weak 'carinal flanges' on the
labial and lingual surfaces (which are preeminent at the mid-crown).
This suite of morphologies is also present in an unnamed Valanginian
(Lower Cretaceous) plesiosuchinan from France. However, the Sicilian
tooth differs from these taxa in having more pronounced carinae, and
faint apicobasally aligned enamel ridges. It also differs from P.
manselii in having more extensive 'carinal flanges' on the labial
surface. The specimen extends the known geological range of
Metriorhynchidae and Thalattosuchia by approximately 7–8 million
years. This overturns previous hypotheses of Metriorhynchidae becoming
extinct early in the Early Cretaceous.
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