Actinia equina, the beadlet anemone, is one of the most common and well-studied sea anemones in European coastal waters (family Actiniidae), a robust, solitary polyp found in intertidal and shallow subtidal zones capable of retracting its tentacles during aerial exposure at low tide. The species captures prey including small invertebrates and fish with nematocyst-laden tentacles and exhibits agonistic behavior including chemical and physical combat between neighboring individuals. Its genome has been sequenced, revealing insights into anemone immunity, venom gene evolution, and stress responses. It is also widely used in toxinological research due to its diverse suite of pore-forming toxins.