Aequorea victoria
"Aequorea" species can be fairly difficult to tell apart, as the morphological features on which identifications are made are mostly the numbers of tentacles, numbers of radial canals, numbers of marginal statocysts, and size. These features are fairly plastic, and the numbers of tentacles and radial canals increase in all species of "Aequorea" with size. One other species is occasionally found in the same geographical range as "Aequorea victoria"; this other form has been called "Aequorea coerulescens". While "A. coerulescens" is apparently generally found offshore in the eastern Pacific Ocean, rare specimens have been collected in central California and in Friday Harbor, North Puget Sound. While morphologically similar to "Aequorea victoria", the "Aequorea coerulescens" form is larger (roughly the size of a dinner plate) with many more radial canals. Animals of sizes intermediate between these two forms are also rather intermediate in appearance, making morphological identifications difficult.