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Robust Sea Squirt

Atriolum robustum


Also known as Colonial Ascidians, Compound Ascidians, Robust Tunicate, Golden Sea Squirt, Soft Sea Squirt, Urn Sea Squirt and Urn Ascidian. They feed on suspended plankton and detritus, and grow to a length of about 2.5cm. These urn-shaped ascidians have numerous oral siphons. Often confused with Didemnum molle, which has minute oral siphons. They vary in color from white, orange to bright green. The green color inside them is the result of being inhabited by blue-green algae.


Found in groups in shallow, sheltered water growing on dead coral. Widespread in the Indo-Pacific region.


I photographed this small group of squirts at a dive site called Basti's Reef, off the western coast of Samal Island, Philippines. I was about 10m deep when I took these photos.

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Blogie 9 years ago

Thank you, Nopayahnah!

Maria dB
Maria dB 9 years ago

Really nice!

Spotted by

Davao Del Norte, Philippines

Spotted on Jan 12, 2012
Submitted on Jan 12, 2012

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