Intertidal Invertebrates of the Monterey Bay Area, California

Compiled & photographed by Gary McDonald, Long Marine Laboratory, University of California, Santa Cruz

Description: May be mauve, buff or purple; forming an encrustation 2-3mm thick on rocks; oscules 1-3mm in diameter, rather regularly spaced, usually elevated 1-5mm on tubes like small volcanoes. As with many sponges, the spicules must be examined identify this species.
Notes: Occurs higher in the intertidal than most other sponges in our area, and also where there is more light than most other sponges in our area prefer.