Sanctuary Integrated Monitoring Network
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Leathery compound tunicate. The status of the genus is unclear, so this is either <em>Eudistoma psammion</em> or <em>Archidistoma psammion</em>, depending on which taxonomic source you use. Can be brown, purple or kind of grey, with raised rings on the surface. Thick and can be massive. Often with sand in the tunic. Not sure if the knobs are an internal growth strategy or if it is driven by overgrowing other species or terrain.

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The SIMoN photo library contains 5202 digital images of animals, habitats, locations, and issues of the Cordell Bank, Gulf of Farallones and Monterey Bay National Marine Sanctuary. Use the search options below to find images of interest. You will be able to browse thumbnails of images then download a high resolution version. For any questions, contact Dr. Steve Lonhart by email (Steve.Lonhart at

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Select from the list of locations where SIMoN staff have taken photos. Once a location has been selected, if there are associated sites within that location they will appear as a pull-down menu, allowing you to further restrict your search.