Vampire Crab (Geosesarma dennerle) – A Little Dracula in Your Terrarium
Vampire Crab (Geosesarma dennerle Ng, Schubart & Lukhaup, 2015), is a terrestrial crab commonly found in commercial and home cultures. It is the “iconic” crab of the Geosesarma genus, reaching a size of 3 to 5 cm. Although it was only described scientifically in 2015, it had already been raised in homes and was common in trade. It is most similar to species such as Geosesarma hagen Ng, Schubart & Lukhaup, 2015, Geosesarma noduliferum De Man, 1892, and Geosesarma bicolor Ng and Davie, 1995.
Habitat
This species is endemic to central Java, Indonesia.
Naming
The species is named after the aquarium supply company Dennerle, which supported one of the describing authors’ (Christian Lukhaup) study in Java.
What Does the Vampire Crab Look Like?
The vampire crab (Geosesarma dennerle) has purple-brown or purple-black legs. Its carapace is clearly divided into two colors: purple-brown or purple-black and yellow. The pincers are purple or purple-brown, and the eyes are yellow or white-yellow. Some individuals have less yellow on the carapace. The coloration of crabs depends on individual characteristics, the time before molting, and age. Young individuals are brown with yellow spots or purple-brown with yellow spots. As they grow, their coloration changes.
Living Conditions
This upland species inhabits river valleys of tropical forests and is closely associated with aquatic environments. It hides among stones and roots or digs burrows in loose soil. It readily uses mulch as shelter. Young individuals spend more time in and around water.
What Does the Vampire Crab Eat?
Geosesarma dennerle primarily feeds on small invertebrates, enjoying the active hunt. It also eats plant parts and carrion, though it prefers freshly hunted prey. In captivity, it is worth feeding it cricket hatchlings, cockroach hatchlings, chironomid larvae, and other aquatic invertebrate larvae. Aquarium fish foods such as Tropical Ichtio-vit, Tropical Bio-vit, and Tropical Ovo-vit work well. Soft fruits like bananas and mangoes can add variety to its diet. Although omnivorous, invertebrates form the basis of its diet.
Activity
Vampire crabs are shy animals, active around the clock, both day and night. They are more active in larger groups, being a herd species.
Interesting Facts
The vampire crab (Geosesarma dennerle) is often confused with other similar but not yet scientifically described species. Interbreeding with Geosesarma hagen has been observed in captivity. In the wild, the two crab species are found in locations only about 10 km apart, suggesting that such interbreeding may also occur naturally, though this phenomenon has not been scientifically described.
Literature
Personal Observations and Experiences
Peter K. L. Ng, Christoph D. Schubart & Christian Lukhaup (2015). New species of “vampire crabs” (Geosesarma De Man, 1892) from central Java, Indonesia, and the identity of Sesarma (Geosesarma) nodulifera De Man, 1892 (Crustacea, Brachyura, Thoracotremata, Sesarmidae). Raffles Bulletin of Zoology.
Yeo, D.C.J. & Ng, P.K.L. (1999). A New Species of Geosesarma (Crustacea: Decapoda: Brachyura: Grapsidae) from Pulau Tioman, Peninsular Malaysia. The Raffles Bulletin of Zoology Supplements (6), 189-196.
Ng, P.K.L. (1986). Preliminary descriptions of 17 new freshwater crabs of the genera Geosesarma, Parathelphusa, Johora and Stoliczia (Crustacea Decapoda, Brachyura) from South East Asia. Journal of the Singapore National Academy of Science. 15: 36–44.
