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Rukwasuchus, new crocodyliform from Cretaceous of Tanzania

From: Ben Creisler

In the new Journal of Vertebrate Paleontology:

Joseph J. W. Sertich & Patrick M. O’Connor (2014)
A new crocodyliform from the middle Cretaceous Galula Formation,
southwestern Tanzania.
Journal of Vertebrate Paleontology 34(3): 576-596

A new taxon of peirosaurid crocodyliform, Rukwasuchus yajabalijekundu,
gen. et sp. nov., is described on the basis of a well-preserved
partial skull from the middle Cretaceous Galula Formation exposed in
southwestern Tanzania. The skull is distinguished from those of other
crocodyliforms by the presence of a mediolaterally narrow, elongate,
and septate internal narial fenestra (choana) located anteriorly on
the pterygoid; a markedly depressed posterior border of the parietal,
excluding the supraoccipital from the dorsal cranial table; and a
ventrally directed descending process of the postorbital with a
well-developed posteroventral process. The lateral surface of the
braincase is exquisitely preserved and includes a well-developed
laterosphenoid bridge dividing the foramina for the three primary
branches of the trigeminal nerve. In overall morphology, the holotype
skull and isolated teeth compare closely with Hamadasuchus rebouli
from the middle Cretaceous Kem Kem Beds of Morocco. Reevaluation of
the problematic putative African peirosaurid taxa Stolokrosuchus
lapparenti and Trematochampsa taqueti reveal a number of derived
cranial characters shared with Peirosauridae and Araripesuchus. A
close relationship between Rukwasuchus and other African members of
Peirosauridae is supported by a parsimony analysis of Crocodyliformes.
As the only known sub-Saharan peirosaurid from Africa, Rukwasuchus
represents the only link between middle Cretaceous southern vertebrate
faunas and much more abundant, taxonomically diverse, and potentially
penecontemporaneous faunas from northern Africa.