Growing in sand, low tide zone
In the encrusting coralline, there are a bunch of little tentacle
A veritable seaweed "garden," photographed among the tidepools north of Greyhound Rock in coastal Santa Cruz County, CA. Among the seaweeds here is Pyropia perforata. This is visible as very thin, cellophane-like sheets of algae covering some Little Turkish Washcloth in the lower left-hand corner of the picture.