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Triassic dicynodont Stahleckeria found in Namibia



From: Ben Creisler
bcreisler@gmail.com

Apologies for a dumb typo in the subject line, s.b. Namibia.For
searching the DML database, spellings matter.

===

Non-dino, but may be of interest, including evidence of rauisuchian:



Fernando Abdala, Claudia A. Marsicano, Roger M.H. Smith & Roger Swart (2012)
Strengthening Western Gondwanan Correlations: a Brazilian Dicynodont
(Synapsida, Anomodontia) in the Middle Triassic of Namibia.
Gondwana Research (advance online publication)
http://dx.doi.org/10.1016/j.gr.2012.07.011
http://www.sciencedirect.com/science/article/pii/S1342937X12002523?v=s5



Terrestrial Middle Triassic strata occur throughout continental
Africa, and are particularly well exposed in South Africa, Tanzania,
Zambia, and Namibia. The youngest age for all these African deposits
is widely accepted as early Middle Triassic (Anisian). Fossils
collected recently from the uppermost strata of the upper Omingonde
Formation in Namibia highlighted the presence of Chiniquodon, a
carnivorous cynodont previously only found in Ladinian-Carnian aged
rocks of South America. In addition, work in progress indicates that a
large archosaur, originally reported as Erythrosuchus, also discovered
from levels close to the top of this unit, is in fact a rauisuchian, a
group of archosaurs well known from Ladinian-Carnian beds of southern
South America. Here we present the first record of the tuskless
dicynodont Stahleckeria potens, from the top of the upper Omingonde
Formation in central Namibia. This taxon was up until now only known
from the Ladinian Dinodontosaurus Assemblage Zone of the Santa Maria
Formation in southern Brazil. Thus, compelling evidence for a Ladinian
age for the upper levels of the upper Omingonde Formation is provided
by two therapsid and one archosaur taxa. The tetrapod fauna of the
upper Omingonde Formation partially fills the gap of the
well-documented hiatus (Ladinian gap), prevalent throughout the Karoo
basins of south and central Africa. The presence of the same therapsid
taxa in the Namibian Waterberg Basin and the Paraná Basin of Brazil
during Middle Triassic suggests that these basins were
biogeographically linked through a series of interconnecting lowlands,
with no major ecological, climatic and/or physical barriers.