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Lophozozymus pictor


Lophozozymus pictor (Fabricius, 1798)

Family Name: Xanthidae
Synonyms: Cancer pictor (Fabricius, 1798)
Taxonomic Group: Invertebrates (Crustacean, Crab and Prawn)
Common Name: Mosaic Reef Crab


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Size 8 cm
Description A beautifully coloured crab with black tips to the pincers, red legs, and a mosaic pattern of red, white and black markings on the back of the shell

Ecology, Habitat & Location

Ecological Notes Found in littoral and sublittoral rocky and coral rubble areas and coral reefs.
Habitats Coral Reef, Marine, Rocky Shore
Distribution Recorded from the Indian Ocean, Singapore, Philippines, Thailand, Vietnam, China, Japan, Ambon (Indonesia), Western Australia.


Trends & Threats Loss of rocky shore and coral reef habitats due as a result of dumping, land reclamation and coastal development.
Scientific Interest & Potential Value This is one of the most poisonous crabs in the world. The neurotoxin it possesses is not denatured by heat during cooking, and can easily kill a man. In fact, the poison in an average crab has been estimated to be able to kill tens of thousands of mice - what it means in human terms is that this will kill a large number of people! The source of its toxin is from its food, and may include poisonous sea cucumber species which it is known to feed on. 
Conservation Notes The conservation of rocky shores and coral reefs will help this species to maintain its population in Singapore waters. It is displaced by conversion f shores to artificial forms such as sea walls or embankments.


Species Status Native
Singapore Red Data Book Status Endangered (EN) [2008]




References Davison, G.W.H., Ng, P.K.L. & Ho, H.C (Eds.). 2008. The Singapore Red Data Book (2nd Edition). Singapore: Nature Society (Singapore). 285pp


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Species record last updated on: 16 March 2022.