The marbled crayfish is able to reproduce on its own, and experts fear that its proliferation worldwide threatens other species.
Originally, it comes from Florida, but it has since spread to other parts of North America as well as Europe, Japan, and Madagascar. It is still legal to sell them in North America but the European Union has banned them, mostly due to concerns about their environmental impact as an invasive species that could crowd out or compete directly with native crayfish species.
Procambarus virginalis, as it is properly called, first burst onto the scene three decades ago, and its impact has become a growing concern for experts worldwide. Officially, it is a separate species from the slough crayfish, and it is causing the most concern in Madagascar where authorities believe it threatens as many as seven species.
“Marmorkrebs are the only known decapod crustaceans to reproduce only by parthenogenesis,” reads a Wikipedia excerpt. “All individuals are female, and the offspring are genetically identical to the parent. Marmorkrebs are triploid animals, which may be the main reason for their parthenogenetic reproduction. Marmorkrebs are thus a model for the rapid generation of species. Because marmorkrebs are genetically identical, easy to care for, and reproduce at high rates, they are a potential model organism, particularly for studying development. A major drawback, however, is the long generation time (several months) compared to other research organisms.”