Of all the gelatinous creatures visiting Monterey Bay, the purple-striped jelly is certainly among the most recognizable and spectacular. Based on certain morphological characters, a taxonomic revision has placed this species (formerly Pelagia colorata) in the genus Chrysaora. With a bell of up to 70 cm diameter, usually streaked with a radial pattern of stripes, and long, flowing oral arms, this jelly is quite impressive. The four frilly oral arms have a coiled appearance. Eight marginal tentacles alternate with eight sensory rhopalia. The tentacles are well armed with nematocysts and can produce a relatively painful sting. Although large specimens are typically endowed with very distinct purple pigment patterns, younger individuals have a pale pinkish bell that lacks the dramatic stripes and patterns of adults. Youngsters also have long, thin, dark maroon tentacles that assume a more subdued coloration by adulthood. Young adults like the one in the second photo can be endowed with truly impressive oral arms, sometimes as long as 4 to 5 meters. Very old individuals often lack the long flowing oral arms and have thickened, pale tentacles. The photos here show a progression from a jelly toddler to a withered old-timer.
Unlike sea nettles and moon jellies, purple-striped jellies are not seen in large surface aggregations. Juvenile slender crabs (Cancer gracilis, bottom photo) often make homes of this jelly and travel with their host until ready to assume a benthic existence. A wide variety of zooplankton serve as prey, including copepods, larval fish, ctenophores, salps, other scyphomedusa, and fish eggs. Chrysaora colorata has a relatively limited range primarily off the coast of California. It is possible to establish polyps and culture this species in captivity, although it’s not as easy as some other species. When provided appropriate aquarium conditions (such as a kreisel tank), the medusae do well under captive conditions. Purple-striped jellies are a popular species for display at public aquariums, but cultured individuals never attain the spectacular dimensions or coloration of their wild counterparts.