(photos of Chris Grossman, founder of diver.net website, USA: specimens from California)
This spectacular species known from Californian waters could be easily identified on photos. Although originally described as a member of the genus Urticina from Baja California the species certainly is not an Urticina. The nematocysts in the actinopharynx are much smaller than in any Urticina species and regularly hexamerous arrangement of the tentacles and mesenteries is another difference from Urticina. For discussion see recent revision of Pacific species of Urticina:
SANAMYAN N.P., SANAMYAN K.E., 2006. The genera Urticina and Cribrinopsis (Anthozoa: Actiniaria) from the North-Western Pacific. Journal of Natural History, 40(7-8): 359-393.
