From Discovery News:
Razor-Toothed Meat-Eater Was Mammal Relative
With its saw-like teeth and sleek body, this voracious predator was equipped to rip flesh from prey.
By Jennifer Viegas
Mon Dec 12, 2011 09:39 AM ET
THE GIST
A newly discovered ancient mammal-like animal was a sleek predator with an incredible appetite for meat.
The animal was a hypercarnivore, meaning over 70 percent of its diet was meat.
The protomammal died out, but another group — the cynodonts — gave rise to mammals some 35 million years later.A newly identified primitive mammal-like animal was agile, sleek and had a voracious appetite for meat.
The animal, identified as a varanopid pelycosaur and part of the genus Aerosaurus, looked like today’s Komodo dragons, but was actually more closely related to mammals, according to a study published in the journal Naturwissenschaften (The Science of Nature).
“Our varanopid was probably about the size of an adult Nile monitor found in Africa,” co-author Sean Modesto told Discovery News.
“It would have looked superficially like one too. The curvature of the teeth (the tips curve back towards the throat) and the serrations on the cutting edges of these teeth suggest that the animal was equipped to rip flesh from vertebrate prey.”
One of the world’s most successful fossil hunters, Roger Smith, found and collected the specimen, which consists of a partial skull and jaw. Smith, another co-author, discovered the remains in rocks from the Pristerognathus Assemblage Zone of the Beaufort Group, South Africa.
… It lived about 260 million years ago during the Permian Period and was part of “the first wave of creatures on the evolutionary line to mammals,” said Modesto, an associate professor of biology at Cape Breton University. …
Aerosaurus eventually died out. Another protomammal group, called the cynodonts, gave rise to mammals. The cynodonts appeared some 1-3 million years after the lifetime of the newly identified varanopid. It then took another 35 million years of evolution before the first actual mammals emerged.
Dear Kitty. Some blog 
No gap in the Middle Permian record of terrestrial vertebrates
Michael J. Benton, School of Earth Sciences, University of Bristol, Bristol BS8 1RJ, UK. Posted online 2 Mar. 2012; doi: 10.1130/G32669.1.
New work on fossil reptiles from Russia shows a more continuous evolutionary record than had been assumed. A key concern about the fossil record is that it is incomplete. Major gaps — times when no fossils were preserved — can hide the detail of certain episodes in the history of life. During the Permian period 300-250 million years ago, the basis of modern terrestrial ecosystem was established. Worldwide climates became warmer and drier, and reptiles rose in importance. The first plant-eating reptiles appeared, and Late Permian ecosystems were broadly comparable to modern ones. Until recently, however, the Permian record of reptiles was said to be incomplete, with a gap of up to 5 million years. This was because paleontologists had to look at rock successions from different continents, and it seemed there was a major time hiatus between the well-known Lower Permian successions of North America and the Middle and Upper Permian successions of South Africa and Russia. New dating evidence shows that the Russian rock record overlaps the North American record, and the gap is closed. We can study the story of change in terrestrial ecosystems through the Permian without a major lack of knowledge.
http://www.alphagalileo.org/ViewItem.aspx?ItemId=118164&CultureCode=en
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