A Race of Mutant Americans is Taking Over Europe

Self-cloning mutant crayfish from America are taking over Europe's lakes, rivers, and streams and have now even reached Africa.

The six-inch-long marbled crayfish is a species that did not exist just 25 years ago. It appears to be a mutation of the Slough Crayfish, Procambarus fallax, which lives only in the tributaries of the Satilla River in Florida and Georgia.

Scooped up for the aquarium trade, a mutation seems to have occurred about 25 years ago enabling the crayfish to produce asexually.

All marbled crayfish are female.

The Marbled Crayfish has now been declared a species in its own right -- Procambarus virginalis. Slough Crayfish and Marbled Crayfish can produce no young together; this is a true species separation, albeit, where one is self-fertilizing clone.