Promissum

Promissum; Temporal range: Upper Ordovician PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Infraphylum:	Agnatha
Class:	†Conodonta
Family:	†Balognathidae
Genus:	†Promissum; Kovacs-Endrody, 1986
Species:	†P. pulchrum
Binomial name
	†Promissum pulchrum; Kovacs-Endrody, 1986

Promissum is an extinct genus of conodonts, primitive chordates, that lived during the Upper Ordovician period.

A conodont, Promissum had a primitive mouth under its eyes with mineralized teeth, which are both typical for conodonts. It had a primitive backbone and 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 40 cm (16 inch) in length.^[2]

Well-preserved specimens were discovered in the Soom shale of South Africa in 1994.^[3]

Promissum 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. Bibcode:1998JGSoc.155..447G. doi:10.1144/gsjgs.155.3.0447. S2CID 129236534.
^ 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 (6525): 800–803. Bibcode:1995Natur.374..800G. doi:10.1038/374800a0. S2CID 4342260.