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Patagonian squamates from Cretaceous onward (free pdf)

From: Ben Creisler

A recent issue of the Biological Journal of the Linnean Society (103(2))
was devoted to Patagonia as Palaeogeography and Palaeoclimatology of
Patagonia: Implications for Biodiversity
The papers can be downloaded for free at:

A number have content about Mesozoic climate, flora, and fauna.  I would
point out in particular:

Evolution of Squamata Reptiles in Patagonia based on the fossil record.
Biological Journal of the Linnean Society 103(2): 441?457 
DOI: 10.1111/j.1095-8312.2011.01691.x

The Squamata, a vertebrate group that includes ?lizards?, amphisbaenians
and snakes, have inhabited Patagonia since the Late Cretaceous. The
Mesozoic record comprises an iguanian, a scleroglossan and a great
diversity of snakes that include, among others, the most primitive
terrestrial forms. Snakes were also well diversified in the Palaeogene,
with fossils of madtsoiids and boids (including the oldest record of the
extant Boa) found as far south as 46°S, following the then dominant
subtropical conditions in the region. The Palaeogene record comprises
small, medium-sized and large forms. The only boids that persisted at the
beginning of the Neogene are all small forms, suggesting colder
temperatures than during the Palaeogene. The oldest South American
?colubrids? made their first appearance at this time, reaching latitudes
south of the current Patagonian distribution (50°S). The Neogene record
also includes the first occurrence of extant iguanians (Pristidactylus and
Liolaemus) and teiids (Tupinambis). The latter reached the southernmost
distribution of its evolutionary history during the Miocene. The
distribution of boids, ?colubrids? and tupinambine teiids at higher
latitudes than at present indicates warmer conditions during the Miocene.
The uplift of the Patagonian Andes, followed by a decrease in temperature
and an increase in desertification, induced a strong contraction in the
distribution of tupinambine teiids to northern regions of Patagonia and
even forced the complete disappearance of boids from this region. In
contrast, these changes appear to have favoured the diversification of
iguanian genera on both sides of the Patagonian Andes. 

This paper was mentioned some months back but the pdf is now free: 
A. G. Sennikov (2011)
New tanystropheids (Reptilia: Archosauromorpha) from the Triassic of
Europe. Paleontological Journal 45(1): 90-104 
DOI: 10.1134/S0031030111010151

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