Iberian Freshwater Crab Potamon ibericum

Potamon ibericum — despite its name — is principally distributed across the Caucasus region, Black Sea coastal drainages, Turkey, and parts of the Middle East rather than the Iberian Peninsula. It inhabits rivers, streams, and lake margins with cool to warm temperate water, displaying a broad, robust build with large chelae and a smooth olive-brown to reddish-brown carapace.

In captivity it requires spacious, cool, clean aquaria with rocky hiding structures and strong filtration. Like most potamid crabs, it is territorial and aggressive toward conspecifics, making single-specimen maintenance the simplest approach. In very large aquaria, a male-female pair may coexist if shelters are plentiful.

P. ibericum is omnivorous and adapts well to captive feeding regimes including sinking pellets, frozen meaty foods, blanched vegetables, and live or frozen invertebrates. It is a direct developer: females carry a clutch of large eggs under the abdominal flap until fully formed juveniles are released, bypassing any free-swimming larval phase. Its relatively robust build and adaptability to a range of hard, alkaline water conditions makes it more forgiving than some potamid species.

Water: 16–24°C, pH 7.2–8.2, GH 8–20, KH 4–14; cool; hard alkaline water preferred; high oxygenation. Tank: minimum 80 L; large rocky caves, coarse gravel, strong filtration; secure lid; no supplemental heating in cool rooms. Feeding: omnivore — sinking pellets, frozen bloodworm, mussel, blanched vegetables, snails; feed every 1–2 days. Breeding: direct developer; female broods large-yolked eggs; miniature juveniles fully aquatic from hatching. Compatibility: one per tank; territorial and predatory; do not house with invertebrates or small fish.