Purple arm vampire crab

Care at a glance

Overview

Keep a colony with more females than males in a species paludarium of 38 liters or more with mostly land. They are mostly peaceful toward their own kind when there are enough hides, but they take shrimp, snails and small fish and fight other crabs, so give them no tank mates. Hold the water at 24 to 28 C, pH 7 to 8, and never add copper. Feed sinking pellets, dried leaves, fruit and blanched vegetables plus protein like frozen bloodworm, small insects or bits of fish, and offer cuttlebone for molting.

In the wild

Purple arm vampire crabs come from West Java around Bogor, where they live on the forest floor beside streams and turn up in rice fields, tea gardens and parks near villages. They are semi-terrestrial, so they need a paludarium rather than an aquarium: 38 liters or more, 70 to 80 percent land with a shallow freshwater pool, fine damp sand, moss, bark and leaf litter to hide in, and a tight lid to keep humidity at 75 to 90 percent. Keep the water at 24 to 28 C and on the alkaline side, pH 7 to 8.

Good to know

Geosesarma noduliferum was described by De Man in 1892 from the Tjiparidi River near Buitenzorg, today's Bogor, and it is the type species of the whole vampire crab genus. Males reach about 1.5 cm across the carapace, with a violet to blue body, purple claws, and pale yellow or white eyes. Its identity was pinned down in 2015 by Ng, Schubart and Lukhaup, who described G. dennerle and G. hagen in the same paper. The trade name Geosesarma bogorensis, which shops often attach to this crab, is not a described species, though it is recorded as a nomen nudum credited to Whitaker, Roberts, Spicer and Turner 2026. It develops directly, with the female releasing fully formed young into fresh water.

Common questions

Related species

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  0.6 in (1.5 cm) · 10 gal (38 L)

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• 

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• 

  Purple vampire crab

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  Blue-leg vampire crab

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  2 in (5 cm) · 10 gal (38 L)

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• 

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• 

  Red vampire crab

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  2 in (5 cm) · 10 gal (38 L)

  2 in (5 cm)10 gal (38 L)72–82°F (22–28°C)