''Stellamedusa'' is a genus of

jellyfish Jellyfish, also known as sea jellies or simply jellies, are the #Life cycle, medusa-phase of certain gelatinous members of the subphylum Medusozoa, which is a major part of the phylum Cnidaria. Jellyfish are mainly free-swimming marine animal ...

. The genus is monotypic with a single species recognized, ''Stellamedusa ventana''. The species was first described in the ''Journal of the Marine Biological Association'' in 2004 by Kevin Raskoff and George Matsumoto of the Monterey Bay Aquarium Research Institute. As of February 2004, seven specimens have been observed, five off the

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

coast in

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and two in the

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. Unlike most medusae, they lack marginal tentacles. Specimens so far found reach almost 10 cm in diameter, which is large for a scyphomedusa. The bell is blue-white in colour. The exumbrella is white, and this and the four oral arms are covered with large nematocyst-laden projections filled with stinging cells, enabling the jelly to capture food items of a variety of sizes; it seems to prefer large prey, up to half its size, which is unusual in jellies that capture prey with their bells rather than with tentacles. The bumpy appearance that the stinging cells give to the jelly led to its common name. The species name comes from the remotely operated vehicle ( ROV) ''Ventana'', a deep-diving

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that first recorded the jelly on video in 1990.Raskoff, K.A., Matsumoto, G.I., 2004. ''Stellamedusa ventana'', a new mesopelagic scyphomedusa from the eastern Pacific representing a new subfamily the Stellamedusinae. Journal of the Marine Biological Association of the United Kingdom 84, 37–42. ''Stellamedusa ventana'' has so far been observed only at mesopelagic depths, i.e. between 150 and 550 meters. At these depths, sunlight does not penetrate, but there is still a reasonable amount of oxygen. Many species of jellyfishes live at this level, and it is likely that ''S. ventana'' feeds primarily on other jellies. Another large jellyfish discovered by the same researchers is '' Tiburonia granrojo''.

References

External links

MBARI press release about the discovery of ''S. ventana''
Ulmaridae Scyphozoan genera Cnidarians of the Pacific Ocean Marine fauna of North America Marine fauna of the Gulf of California Western North American coastal fauna Fauna of California Monotypic cnidarian genera {{Scyphozoa-stub