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Triassic vertebrate assemblage, Argentina + Cretaceous vertebrate fauna, India + tracks, Namibia



Ben Creisler
bcreisler@gmail.com


A number of new papers:

Ricardo N. Martínez, Cecilia Apaldetti, Gustavo Correa, Carina E.
Colombi, Paula Santi Malnis, Angel Praderio, Diego Abelín, Laura G.
Benegas, Andrea Aguilar-Cameo &  Oscar A. Alcober (2015)
A new late Triassic vertebrate assemblage from northwestern Argentina.
Ameghiniana (advance online publication)
doi:10.5710/AMGH.27.04.2015.2889
http://www.ameghiniana.org.ar/index.php/ameghiniana/article/view/1005

The Quebrada del Barro Formation (QBF) is part of the continental
Marayes-El Carrizal Basin, in NW Argentina. Here we report a diverse
faunal assemblage recently discovered at the Quebrada del Barro
Formation, along with a preliminary discussion of the taxonomic status
and affinities of numerous vertebrate specimens found at two
localities of this unit. The new vertebrate association includes
remains of at least 12 different new species related to six major
vertebrate groups: Cynodontia, Testudinata, Sphenodontia,
Pseudosuchia, Pterosauria, and Dinosauromorpha. The most abundant
specimens in this faunal assemblage are opisthodontian sphenodonts,
tritheledontid cynodonts and basal sauropodomorph dinosaurs, but the
assemblage also includes diagnostic remains of lagerpetid
dinosauromorphs, theropods, pterosaurs, basal crocodylomorphs, and
stem testudinatans. Several of these groups have also been reported
for the Los Colorados Formation (LCF), although the two units differ
in their taxonomic content at the species level and in the relative
abundance of different taxonomic groups. A comparison of these two
faunal assemblage suggest the fauna of QBF is younger than that of LCF
and we tentatively assess a late Norian–Rhaetian age for the QBF. Some
of the specimens reported here are known from well-preserved specimens
and contain important new information for understanding the evolution
of these groups, which underscores the relevance of the QBF fauna for
assessing the dynamics of the major groups of vertebrates that
dominated the terrestrial ecosystems during the early Mesozoic in
Pangea.

===

Omkar Verma (2015)
Cretaceous vertebrate fauna of the Cauvery Basin, southern India:
Palaeodiversity and palaeobiogeographic implications.
Palaeogeography, Palaeoclimatology, Palaeoecology (advance online publication)
doi:10.1016/j.palaeo.2015.04.021
http://www.sciencedirect.com/science/article/pii/S0031018215002229

Highlights

Marine and non-marine vertebrates occur in Cretaceous sequences of
Cauvery Basin.
Marine vertebrates show a wide geographic distribution and a vast
marine territory.
Non-marine vertebrates showing mixed Gondwanan and Laurasian affinities.
Fauna indicates close links between India and Madagascar in the latest
Cretaceous.

Abstract

The vertebrate fauna from the late Albian to Maastrichtian succession
of the Cauvery Basin, south India has been known since 1845, but it
received only scant attention as compared to the vertebrates already
known from the Deccan volcanic province of peninsular India. Recent
fossil discoveries appear to support the emergence of significantly
diverse marine and non-marine vertebrates comprising fishes, frogs,
reptiles (ichthyosaurs, plesiosaurs, turtles, crocodiles and
dinosaurs) and a mammal from the Cauvery Basin have revived the
interest in the fauna of the basin as it has significant implications
for understanding the palaeobiogeography of India. The latest Albian
to Turonian marine vertebrates such as sharks, ichthyosaurs and
plesiosaurs show a wide geographic distribution and marine territory,
while sharks are typically cooler water fauna of high palaeolatitudes.
The latest Maastrichtian non-marine vertebrates especially turtles,
crocodiles, dinosaurs and a mammal are considered to show mixed
Gondwanan and Laurasian affinities thus providing new lines of
evidence in favour of a latest Cretaceous biotic links between India
and the neighbouring continents. An overview of the vertebrate faunal
diversity of the Cretaceous sequences of the Cauvery Basin and its
palaeobiogeographic considerations are presented.

==

Simone D’Orazi Porchetti & Alexander Wagensommer (2015)
A vertebrate trackway from the Twyfelfontein Formation (Lower
Cretaceous), Damaraland, Namibia.
Paläontologische Zeitschrift (advance online publication)
DOI: 10.1007/s12542-015-0264-6
http://link.springer.com/article/10.1007/s12542-015-0264-6

A trackway of 22 footprints is the first definite evidence of
vertebrate life from the Main Aeolian Unit of the Twyfelfontein
Formation (Lower Cretaceous), Kunene region, Northwestern Namibia.
Footprints were left on the lee slope of an ancient dune in a
hyper-arid, erg-dominated paleo environment. The new material is
reminiscent of the Mesozoic ichnotaxon Brasilichnium, which is
exclusively found on the slip face of sand dunes, from both South and
North America. The Twyfelfontein Formation is considered a lateral
equivalent of the Brazilian Botucatu Formation in which Brasilichnium
is a common trace fossil, but correlation was formerly based
exclusively on sedimentologic and lithostratigraphic homologies. Aside
from being the first vertebrate evidence from the Cretaceous of
Namibia, and possibly the first African Brasilichnium, this new find
enforces the correlation between the Botucatu and the Twyfelfontein
formations.