Potamon fluviatile crabs' unusual size, up to , and longevity (up to 15 years) are also interpreted as evidence of a long-established population, by analogy with island gigantism. On the island of Malta, "Potamon fluviatile" is rare and restricted to a few locations in the west of the island. On Gozo, there is a single population which inhabits a stretch of river only long. In the Balkan Peninsula, "Potamon fluviatile" is known to occur in Croatia, Montenegro, the Republic of Macedonia, Albania and Greece. There are four species of "Potamon" in the Balkans, and "P. fluviatile" is replaced by "Potamon ibericum" in
Potamon fluviatile the larval stages inside the egg. "Potamon fluviatile" is edible, as indicated by its alternative specific epithet "edulis", and was known to the ancient Greeks; it is probably this species which they depicted on medals found at Agrigento, Sicily. More recently, the species was depicted on the 5¢ coin in the last series of Maltese coins before the introduction of the Euro there in 2007. "Potamon fluviatile" has a generalist diet, feeding on vegetable debris, scraping algae from surfaces, or preying on frogs, tadpoles, and various invertebrates, such as insect larvae, snails or worms. No predator seems to specialise on