Mordacia mordax

Short-headed lamprey
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Cephalaspidomorphi
Order:	Petromyzontiformes
Family:	Petromyzontidae
Subfamily:	Mordaciinae
Genus:	Mordacia
Species:	M. mordax
Binomial name
Mordacia mordax J. Richardson, 1846

The short-headed lamprey, Mordacia mordax, also known as the Australian lamprey and the Murray lamprey, is a species of lamprey that occurs in south-eastern Australia. It has a thin eel-like body up to 50 cm long, with two low dorsal fins on the back half. The skin is blue-gray or brown. Its eyes are small, and located on the top of its head.

Adult short-headed lampreys live at sea and are parasites on other fish. They breed in fresh water, however, migrating up streams in southeastern Australia from Shoalhaven River, New South Wales to Gulf St Vincent, South Australia. The ammocoetes (lamprey larvae) remain in fresh water until metamorphosis, usually migrating to the sea around three to four years after hatching.

References

• Allen, Gerald R. (1989). Freshwater Fishes of Australia. T.F.H. Publications. 
• "Mordacia mordax". Integrated Taxonomic Information System. http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=159747. Retrieved 15 April 2006. 
• Froese, Rainer, and Daniel Pauly, eds. (2006). "Mordacia mordax" in FishBase. 4 2006 version.