Potamon fluviatile Potamon fluviatile Potamon fluviatile is a freshwater crab found in or near wooded streams, rivers and lakes in Southern Europe. It is an omnivore with broad ecological tolerances, and adults typically reach in size during their 10–12 year lifespan. They inhabit burrows and are aggressive, apparently outcompeting native crayfish. "P. fluviatile" has been harvested for food since classical antiquity, and is now threatened by overexploitation. Many of the island populations are particularly vulnerable, and the Maltese subspecies has become a conservation icon. A population in Rome may have been brought there before the founding of the Roman Empire. Adult "Potamon
Potamon fluviatile are right-handed. In the Tosco-Emilian Apennines, "P. fluviatile" is only found south of the watershed, in contrast with the crayfish "Austropotamobius pallipes", which occurs on both sides on the mountains. Although their ranges overlap, the two species do not inhabit the same water courses, apparently because the crab outcompetes the crayfish, which is therefore forced to live in less favourable locations where the crab cannot survive. Non-indigenous crayfish may pose a greater threat to "P. fluviatile" than native crayfish, although the greatest threats remain pollution, overfishing and the draining of wetlands. The natural range of "Potamon fluviatile" is highly fragmented,