talking points for nature guides
crabs text index | photo index
Phylum Arthropoda > Subphylum Crustacea > Class Malacostraca > Order Decapoda > Brachyurans > Superfamily Ocypodoidea > Genus Uca
Porcelain fiddler crab
Austruca annulipes
Family Ocypodidae
updated Dec 2019

Where seen? This small crab with an enlarged pincer that is smooth is sometimes seen on some of our shores. Sandy, silty shores near the low water mark, often near mangroves. It was previously known as Uca annulipes.

Features: Body width 1.5-2cm. Body squarish. The male fiddler crab's enlarged pincer almost twice as long as the body width. The enlarged pincer's outer palm is smooth and does not have a triangular depression. The movable upper finger extends past the immobile lower finger. There is a wide gape between the upper and lower finger. The enlarged pincer's inner palm has a diagonal ridge of bumps. The enlarged pincer is usually pink, sometimes nearly white. Body varies from black to pale, with dark or blue or white stripes. Eyes dark on long stalks yellow, walking legs short various colours from dark to light, orange, brown or reddish.

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

Male displaying, waving his legs
and enlarged pincer
St John's Island, Oct 04

Smooth on the outer side of the pincer.
St John's Island, Oct 04

Bumpy ridge on the inside 'palm' of the pincer

Chek Jawa, Jan 04

Pulau Hantu, Apr 04

Chek Jawa, Jan 04

Porcelain fiddler crabs on Singapore shores
On wildsingapore flickr

Other sightings on Singapore shores

Pulau Ubin Jun, 09
Photo shared by Marcus Ng on flickr.

Pulau Pawai, Dec 09
Photo shared by James Koh on his flickr.

Pulau Semakau South, Feb 16
Photo shared by Heng Pei Yan on facebook.

Terumbu Pempang Laut, Aug 16
Photo shared by Marcus Ng on facebook.



  • 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.
  • 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.
links | references | about | email Ria
Spot errors? Have a question? Want to share your sightings? email Ria I'll be glad to hear from you!
wildfactsheets website©ria tan 2008