Potamon fluviatile as well as on the island of Sicily. Although it used to be found as far north as Lake Garda, "P. fluviatile" no longer occurs north of the River Po. In 1997 a population of "P. fluviatile" was discovered under the ruins of Trajan's Forum in the heart of Rome, living in canals built by the Etruscans which connect to the "Cloaca Maxima". Based on a genetic analysis, which demonstrated that these crabs were similar to those in Greece, researchers believe that they had been brought by the Greeks before the founding of the city, some 3000 years ago. The
Potamon fluviatile "P. fluviatile", but a number of animals take it opportunistically, including rats, foxes, weasels, birds of prey and jays. The most significant predator may be mankind, with individual prospectors able to catch 3,000 to 10,000 in one season. Adults occupy burrows, while smaller individuals shelter under stones. The entrances to the burrows may be more than from the stream's edge and are always above water level. The burrows may be more than long, and probably serve to protect the crabs from extreme cold. "Potamon fluviatile" is an aggressive species, mostly attacking with the larger right claw, since 90% of individuals