This aquatic clone is a crayfish that has no official scientific name yet, but it is known as a marmorkreb, or more commonly as the marbled crayfish. It was discovered in a German aquarium shop in the 1990s. Some crayfish enthusiasts speculate that it is an offshoot of a Procambarus species, but this has not been established as fact.
The gender of marbled crayfish is always female, and they do not need a partner to reproduce—they reproduce parthenogenetically. As their name implies, they feature an attractive brown marbled pattern, which is identical from individual to individual, and as they mature, they develop deep blue legs and even red and green colors in the claws. Their colors can also be affected by diet.
Because these unusual crayfish clone themselves, they are gaining popularity within the scientific community, particularly among scientists working on genetics and stem cell research. In the classroom they are used by biology teachers to demonstrate evolution (and cloning) in a current, real-world environment. Some aquarium hobbyists now use the marbled crayfish as a self-replicating source of feeders for carnivorous fishes of all sizes. Sport fishermen are raising colonies for use as bait, particularly for saltwater fishing, and it is even rumored that this species is being farmed by the Chinese government for use as a source of cheap food for humans!