Aequorea victoria, also sometimes called the crystal jelly, is a bioluminescent hydrozoan jellyfish, or hydromedusa, that is found off the west coast of North America. This species is thought to be synonymous with Aequorea aequorea of Osamu Shimomura, the discoverer of green fluorescent protein (GFP). Shimomura together with Martin Chalfie and Roger Y. Tsien were awarded the 2008 Nobel Prize in Chemistry^[1] for the discovery and development of this protein as an important biological research tool. Originally the victoria species was supposed to designate the variant found in the Pacific, and the aequorea designation was used for specimens found in the Atlantic and Mediterranean. The species name used in GFP purification was later disputed by M.N. Arai and A. Brinckmann-Voss (1980),^[2] who decided to separate them on the basis of 40 specimens collected from around Vancouver Island. Osamu Shimomura notes that this species in general shows great variation: from 1961 to 1988 he collected around 1 million individuals in the waters surrounding the Friday Harbor Laboratories of University of Washington, and in many cases there were pronounced variations in the form of the jellyfish. In September 2009, Aequorea victoria was spotted in the Moray Firth, an unusual occurrence, as crystal jellies had never been seen or reported in British waters. The specimen is now on display in Macduff Marine Aquarium in Aberdeenshire, Scotland.

Description

Aequorea victoria

Aequorea victoria

Aequorea victoria

Aequorea victoria - ventral view with hyperiid amphipod

Aequorea victoria

Almost entirely transparent and colorless, and sometimes difficult to resolve, Aequorea victoria possess a highly contractile mouth and manubrium at the center of up to 100 radial canals that extend to the bell margin. The bell margin is surrounded by uneven tentacles, up to 150 of them in fully-grown specimens. The tentacles possess nematocysts that aid in prey capture, although they have no effect on humans. Specimens larger than 3 cm usually possess gonads for sexual reproduction, which run most of the length of the radial canals and are visible in the photos in this article as whitish thickenings along the radial canals. The bell margin is ringed with the muscular velum, which is typical of hydromedusae, and aids in locomotion through muscular contraction of the bell. Larger specimens are frequently found with symbiotic hyperiid amphipods attached to the subumbrella, or even occasionally living inside the gut or radial canals.

Species range

Aequorea victoria are found along the North American west coast of the Pacific ocean from the Bering Sea to southern California. The medusa part of the life cycle is a pelagic organism, which is budded off a bottom-living polyp in late spring. The medusae can be found floating and swimming both nearshore and offshore in the eastern Pacific Ocean;^[3] this species is particularly common in Puget Sound.