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Phylum Mollusca > Class Bivalvia > Family Arcidae
Barbatia ark clam
Barbatia sp.
Family Arcidae
updated May 2020

Where seen? This little clam is commonly seen stuck under stones on our Southern shores, sometimes a few clustered together. But it is often overlooked as its 'hairy' shell camouflages it well.

About 2.5cm long. The sturdy two-part shell is oval with fine ribs. There is usually a layer of fine brown hairs (called the periostracum) covering the shell. The hairs grow particularly thickly towards the shell opening. The animal is usually firmly attached to the underside of stones and rubble, usually with the shell opening facing the hard surface.

St John's Island, Mar 05

St. John's Island, Feb 11

Barbatia ark clams on Singapore shores
On wildsingapore flickr

Other sightings on Singapore shores

Tuas, Mar 06

Labrador, Oct 14
Photo shared by Loh Kok Sheng on flickr.

Sentosa Serapong, Dec 20
Photo shared by Vincent Choo on facebook.

Pulau Jong, Aug 21
Photo shared by Vincent Choo on facebook.

Terumbu Bemban, May 21
Photo shared by Vincent Choo on facebook.

Beting Bemban Besar, Jul 20
Photo shared by Vincent Choo on facebook.


  • Barbatia species in the Bivalves section by J.M. Poutiers in the FAO Species Identification Guide for Fishery Purposes: The Living Marine Resources of the Western Central Pacific Volume 1: Seaweeds, corals, bivalves and gastropods on the Food and Agriculture Organization of the United Nations (FAO) website.


  • Tan Siong Kiat and Henrietta P. M. Woo, 2010 Preliminary Checklist of The Molluscs of Singapore (pdf), Raffles Museum of Biodiversity Research, National University of Singapore.
  • Tan, K. S. & L. M. Chou, 2000. A Guide to the Common Seashells of Singapore. Singapore Science Centre. 160 pp.
  • Abbott, R. Tucker, 1991. Seashells of South East Asia. Graham Brash, Singapore. 145 pp.
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