African Freshwater Crab Potamonautes lirrangensis

Potamonautes lirrangensis is a fully aquatic freshwater crab distributed across the Congo Basin and adjacent river systems of Central Africa. It inhabits a range of lotic and lentic freshwater environments, from river rapids to swampy margins, and displays a relatively flattened, smooth carapace in warm reddish-brown to tan colouration.

This species is well-suited to captivity in large, well-filtered aquaria. Like other Potamonautes, it is territorial and requires substantial hiding places — rocky caves, overhangs, and submerged hollow logs. Pairs or small groups can sometimes be maintained in very large tanks with abundant territory, but single specimens are easier to manage. Males are typically larger and display broader, more robust chelae.

P. lirrangensis is an opportunistic omnivore, consuming invertebrates, plant material, carrion, and organic detritus. In captivity it thrives on a diet of high-quality sinking pellets, frozen foods, and blanched vegetables. Water quality is important: the Congo River is characterised by extremely soft, acidic conditions in its upper reaches, but aquarium specimens tolerate a broader range than strictly wild-type parameters suggest.

Water: 22–26°C, pH 6.5–7.5, GH 3–15, KH 1–8; high turnover filtration; weekly partial water changes. Tank: minimum 80 L; rocky caves, driftwood, fine sand; subdued lighting; robust filtration; weighted secure lid. Feeding: omnivore — sinking pellets, frozen bloodworm, mussel, blanched vegetables; feed every 1–2 days. Breeding: females brood eggs under abdomen; fully aquatic juveniles; pairs need very large space. Compatibility: one per tank unless very large; predatory on invertebrates; keep only with robust large fish.