Anthopleura sola - Starburst Anemone

This is another photo that the data for is largely lost. The photo was taken in tidepools not far from Half Moon Bay. Per iNaturalist, The Starburst Anemone is found in the north west Pacific Ocean. In the United States it occurs between central California and Baja California. It lives in the lower intertidal zone in rocky habitats, often in the shelter of cracks and crevices. When the tide is out it is often concealed by shell fragments and other particles that adhere to it.

 

Amazingly, Anthopleura sola aggressively defends its territory from other anemones (of same species) which are genetically dissimilar. When A. sola encounters a different genetic colony, the anemones extend specialized tentacles (called acrorhagi). The white tips of acrorhagi have a concentration of stinging cells (nematocytes) and are used solely to deter other colonies from encroaching on their space. The nematocysts sting the ectoderm of the invader, causing tissue necrosis and forcing the competitor to move away.

Done