[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Femur of large abelisaurid theropod from Cretaceous of Morocco (free pdf)



Ben Creisler
bcreisler@gmail.com

A new paper in open access PeerJ:

Alfio Alessandro Chiarenza & Andrea Cau (2016)
A large abelisaurid (Dinosauria, Theropoda) from Morocco and comments
on the Cenomanian theropods from North Africa.
PeerJ 4:e1754
doi: https: // doi.org/10.7717/peerj.1754
https: // peerj.com/articles/1754/
https: // peerj.com/articles/1754.pdf

We describe the partially preserved femur of a large-bodied theropod
dinosaur from the Cenomanian “Kem Kem Compound Assemblage” (KKCA) of
Morocco. The fossil is housed in the Museo Geologico e Paleontologico
“Gaetano Giorgio Gemmellaro” in Palermo (Italy). The specimen is
compared with the theropod fossil record from the KKCA and coeval
assemblages from North Africa. The combination of a distally reclined
head, a not prominent trochanteric shelf, distally placed lesser
trochanter of stout, alariform shape, a stocky shaft with the fourth
trochanter placed proximally, and rugose muscular insertion areas in
the specimen distinguishes it from Carcharodontosaurus, Deltadromeus
and Spinosaurus and supports referral to an abelisaurid. The estimated
body size for the individual from which this femur was derived is
comparable to Carnotaurus and Ekrixinatosaurus (up to 9 meters in
length and 2 tons in body mass). This find confirms that abelisaurids
had reached their largest body size in the “middle Cretaceous,” and
that large abelisaurids coexisted with other giant theropods in
Africa. We review the taxonomic status of the theropods from the
Cenomanian of North Africa, and provisionally restrict the Linnean
binomina Carcharodontosaurus iguidensis and Spinosaurus aegyptiacus to
the type specimens. Based on comparisons among the theropod records
from the Aptian-Cenomanian of South America and Africa, a partial
explanation for the so-called “Stromer’s riddle” (namely, the
coexistence of many large predatory dinosaurs in the “middle
Cretaceous” record from North Africa) is offered in term of taphonomic
artifacts among lineage records that were ecologically and
environmentally non-overlapping. Although morphofunctional and
stratigraphic evidence supports an ecological segregation between
spinosaurids and the other lineages, the co-occurrence of abelisaurids
and carcharodontosaurids, two groups showing several craniodental
convergences that suggest direct resource competition, remains to be
explained.

==

News:

Fossil find reveals just how big carnivorous dinosaur may have grown

http: // 
www3.imperial.ac.uk/newsandeventspggrp/imperialcollege/newssummary/news_29-2-2016-9-34-57