Haliclona permollis, more commonly known as The Purple Intertidal Sponge or Purple Encrusting Sponge is a purple (sometimes pink or grey) sponge with a velvety texture. This sponge is covered with small circular ostia (pores) where water enters and larger osculum where water leaves. The Purple Intertidal Sponge can grow up to 1.6 cm (0.7 in) thick. It lives in the intertidal waters between Southern California and Southern Alaska and can usually be found in waters up to 6m (20ft) deep in the intertidal areas, as well as in tidepools and on rocky shores.
This species is similar to the Breadcrumb Sponge (Halichondria panicea) and both species are frequently found on the rocky shores around Vancouver Island. Similar to other sponges th Purple Intertidal Sponge gets it’s nutrients by constantly moving water through it’s body (which enters through the ostia and leaves via the osculum) and filtering out and ingesting things like bacteria and organic matter.
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