Acanthostega (meaning Spiny Roof) is an extinct labyrinthodont genus, among the first vertebrate animals to have recognizable limbs. It appeared in the Upper Devonian about 365 million years ago, and was anatomically intermediate between lobe-finned fishes and the first tetrapods fully capable of coming onto land.
It had eight digits on each hand (the number of digits on the feet is unclear) linked by webbing. It lacked wrists, and was generally poorly adapted to come onto land. Acanthostega also had a remarkably fish-like shoulder and forelimb.
It had lungs, but its ribs were too short to give support to its chest cavity out of water, and it also had gills which were internal and covered like those of fish, not external and naked like those of some modern amphibians which are almost wholly aquatic.
The fossilized remains are generally well preserved, with the famous fossil by which the significance of this species was discovered being found by Jennifer A. Clack in East Greenland in 1987, though fragments of the skull had been discovered in 1933 by Gunnar Save-Soderbergh and Erik Jarvik/
16.5 x 5 x 3.5 inches high
Now Over 1,000 Items!
PrehistoricStore.com offers the largest selection of replica fossils and other fossil-related products anywhere in the world!
Download a Full Catalog (3MB PDF)
OVER 260 PAGES OF REPLICAS AND MORE!