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Purplelined Nudibranch

Ceratosoma tenue


Also known as Tenue Sea Slug, T-bar Nudibranch, Purple-edged Ceratosoma, Long-tail Ceratosoma. They feed on hydroids, coral, sponges and sea anemones, and grow to a length of about 11cm. This species can easily be mistaken for either of two species in its genus: C. gracillimum and C. trilobatum. The telling difference is the presence of extra lateral lobes in C. tenue. You can see those lobes just behind its head. (See picture #5)


Found singly or in pairs on coral and rocky reefs, in sand and rubble areas, at depths of 2 to 30m. Widespread in the Indo-Pacific region.


Spotted this elongated nudibranch at the Dayang Beach dive site in a little more than 9m of water. It measured approximately 6cm long.

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Blogie 6 years ago

Thanks, Maria! Me too, that's actually my favorite too. :)

Maria dB
Maria dB 6 years ago

especially like the fourth photo!

Davao Del Norte, Philippines

Lat: 6.95, Long: 125.67

Spotted on May 5, 2012
Submitted on May 5, 2012

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