A related species, the Northern Sea Nettle (C. melanaster) is also found in the eastern Pacific, but usually occurs significantly farther north in the Bering Sea and Gulf of Alaska, although it may drift south at least as far as Oregon. It is similar to the Pacific Sea Nettle and has often been confused with it, but, among other differences, the Northern Sea Nettle has an exumbrella (upper, convex surface of the bell) that is pale white and the pale subumbrella (lower, concave surface of the bell) has 16 radiating dark streaks that are absent in the Pacific Sea Nettle (Carlton 2007). Martin et al. (1997) provide comparative descriptions of the Chrysaora species recognized as of 1997. Additional information on some of these species can be found in Larson (1990).