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Slender Sapsucking Slug

Thuridilla gracilis


Also known as Grace Thuridilla and Glazed Thuridilla, this sea slug varies in color, and sometimes does not display those distinctive turquoise spots (as in this specimen). T. gracilis, however, always has orange-colored antennae.


Found widespread in the Indo-Pacific region.


Spotted this hyperactive slug at a depth of 6m. It measured a little over 1cm long and kept bobbing its head up & down as it crawled at a fast clip. This was at Big Ligid Island, Samal, Philippines.

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Blogie 8 years ago

Hi Alice! Actually I have no idea yet. Have to do more research on why Thuridilla species are called "sapsucking slugs".

alicelongmartin 8 years ago

A whole other world. By sap do you mean blood or something sweet?

Spotted by

Davao Del Norte, Philippines

Spotted on Jul 11, 2012
Submitted on Jul 12, 2012

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