Promissum is an extinct genus of primitive chordate that lived in the Ordovician period, about 500 million years ago.[1]
A conodont, Promissum had a primitive mouth under its eyes with mineralized teeth, which are both typical for conodonts, and also a primitive backbone. It probably looked like a small eel or large worm, lacking any kind of fins except for perhaps a small one on the tail. It was relatively large for a conodont, reaching about Template:Convert/cm in length.[2]
Well-preserved specimens were discovered in the Soom shale of South Africa in 1994.[3]
Prosimmum was probably capable of maintaining a cruising speed, but not of bursts of speed.[3]
References[]
- ^ Gabbott, S.E.; Aldridge, R.J.; Theron, J.N. (1998). "Chitinozoan chains and cocoons from the Upper Ordovician Soom Shale lagerstatte, South Africa; implications for affinity". Journal of the Geological Society 155 (3): 447–452. doi: .
- ^ Palmer, D., ed (1999). The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals. London: Marshall Editions. p. 23. ISBN 1-84028-152-9.
- ^ a b Gabbott, S.E.; R. J. Aldridge, J. N. Theron (1995). "A giant conodont with preserved muscle tissue from the Upper Ordovician of South Africa". Nature 374: 800–803. doi: .