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Phylum Mollusca > Class Bivalvia > Family Pteriidae
Sponge finger oyster
Vulsella sp.
Family Pteriidae
updated May 2020
Where seen? This clam is deeply embedded in a sponge, with only the shell opening appearing as a slit on the surface of the sponge. It was previously in Family Malleidae (Hammer oysters).

Features: Slit 1-2cm long, the clam is generally not seen outside a sponge in the wild. It has been seen in several kinds of sponges in Singapore.

Embedded in a Yellow prickly
branching sponge
Terumbu Pempang Laut, May 12

A slit in the sponge is the only
sign of the clam.

Embedded in a Black bath sponge.
Terumbu Semakau, Dec 11

*Species are difficult to positively identify without close examination.
On this website, they are grouped by external features for convenience of display.

Sponge finger oysters on Singapore shores
On wildsingapore flickr


  • 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.
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