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Phylum Arthropoda > Subphylum Crustacea > Class Malacostraca > Order Decapoda > Brachyurans > Superfamily Ocypodoidea > Genus Uca
Orange fiddler crab
Uca vocans
Family Ocypodidae
updated Dec 12
Where seen? This tiny crab with a 'pimply' oversized pincer is commonly seen on our natural undisturbed shores, usually on softer, muddier areas more exposed to wave action than other fiddler crabs. This includes the bottom of swimming lagoons, shores near large boulders.

Features: Body width 2-3cm. The male fiddler crab's enlarged pincer has a bumpy outer face. The tips of the pincers are flattened and sabre-like. The immobile lower finger is orange or yellow and has a long groove on the outside. Body colours and patterns vary: some greenish, others greyish. Their burrows can be half a metre deep!

Sometimes mistaken for the Porcelain fiddler crab (Uca annulipes). More on how to tell apart the fiddler crabs commonly seen on our shores.


Pincer with long groove on the outside,
lower portion and flattened tips.

Pulau Hantu, May 09

From the back.
Chek Jawa, Oct 04

Female and male.
Pasir Ris, Jun 09

Groove on the inside of the pincer.
Pulau Ubin, May 08

Pincer colours may vary.
Chek Jawa, Feb 02

Pulau Ubin, Feb 05

Different coloured backs.
Pulau Ubin, May 08

Females have two small pincers
Pulau Ubin, May 08

Males may be 'right' or 'left' handed.
Pulau Ubin, May 08

Tussel over a female?
Chek Jawa, Mar 11

Orange fiddler crabs on Singapore shores
Photos for free download from wildsingapore flickr

video clips of orange fiddler crabs on Singapore shores

Links

References

  • Ng, Peter K. L. and Daniele Guinot and Peter J. F. Davie, 2008. Systema Brachyurorum: Part 1. An annotated checklist of extant Brachyuran crabs of the world. The Raffles Bulletin of Zoology. Supplement No. 17, 31 Jan 2008. 286 pp. (Online PDF on the Raffles Bulletin of Zoology website)
  • Lim, S., P. Ng, L. Tan, & W. Y. Chin, 1994. Rhythm of the Sea: The Life and Times of Labrador Beach. Division of Biology, School of Science, Nanyang Technological University & Department of Zoology, the National University of Singapore. 160 pp.
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