Flora index
Fauna index
guide to the mangroves of singapore
Peter K L Ng and N Sivasothi (editors)
Orange mud crab
Scylla olivacea
Family Portunidae

up to 18 cm, Indo-West Pacific

This is the most valuable local crab sold in markets (often incorrectly referred to as S. serrata). These crabs are caught in traps or hooked out of their burrows during low tide. These crabs can survive out of water for extended periods as long as they are kept cool. They feed on a variety of animals, usually other shellfish which they crush with their powerful claws.
close-up of claw
S. olivacea

close-up of claw
S. traquebarica

close-up of claw
S. paramamosain

close-up of claw
S. serrata
whole crab
S. olivacea

whole crab
S. traquebarica

whole crab
S. paramamosain

whole crab
S. serrata
There are actually four species of mud crabs in Southeast Asia, three of which are found locally.

The Purple mud crab (S. tranquebarica) can grow very large (ca. 20 cm), usually with distinct purple claws.
A rare species found in sandier areas near mangroves is the Green mud crab (S. paramamosain) (ca. 15 cm), which has orange and green claws and very sharp frontal teeth.

The Giant mud crab (the real S. serrata, locally called the 'Sri Lanka Crab') seems to prefer more saline oceanic waters and has uniformly green or blue claws. This species can grow to 28 cm in carapace width and weigh close to 3 kg—a size and weight never reached by the Singapore species!

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What is mangrove?

The Ecosystem


Indirect uses
Potential uses

About Mangroves
in Singapore

Mangroves to visit
From "A Guide to Mangroves of Singapore", Peter K. L. Ng and N. Sivasothi (editors)
Volume 1: The Ecosystem and Plant Diversity and Volume 2: Animal Diversity
Authors: Kelvin K. P. Lim, Dennis H. Murphy, T. Morgany, N. Sivasothi, Peter K. L. Ng,
B. C. Soong, Hugh T. W. Tan, K. S. Tan & T. K. Tan
BP Guide to Nature Series published by the Singapore Science Centre, sponsored by British Petroleum
2001 Raffles Museum of Biodiversity Research, The National University of Singapore & The Singapore Science Centre