Gobiconodon ostromi was a triconodont mammal found in both North America and Asia during the early Cretaceous. It was rather large for an early Cretaceous mammal, the skull being about 10 cm long.
More like this
Better late than never, I've only recently gotten hold of Zhou et al.'s paper on the enantiornithine bird Pengornis houi, published online in Journal of Anatomy back in January but now available in hard-copy.
May 18, 2008 -- A tiny abalone specimen 5.9 mm in length and approximately 78 million years old (putting it in the middle Campanian Stage of the Late Cretaceous) has been documented from rocks in the Garapito Creek area of Topanga Canyon, Los Angeles County by Lindsey T.
Tyrannosaurid Skeletal Design First Evolved at Small Body Size:
This is one beautiful trike (well, if gobiconodonts actually were eutriconodonts, wich is by no means clear), although it would have been better avoided in real life - to get stung by those poisonous spurs must have been very painful, if not deadly.
The low built, bent legs and the general impression of brute force somehow reminds me of a glen of imaal terrier. Last week I saw a glen terrier trying to turn over a BMW 3-series station wagon. Of course it did not succeed, but the 15 kg dog made the 1500 kg car shake quite a bit!
The ratel/wolverine/tasmanian devil niche seems to have been one of the few large-bodied terrestrial niches that the non-avian dinosaurs never got a hold of, leaving it to the synapsids and the crocs. Perhaps small theropods were just too frail and stiff-bodied to be brawlers.
One wonders what killed the eutriconodonts - they disappeared in the mid-Cretaceous without any apparent reason?