Thimble jellyfish
| Thimble jellyfish | |
|---|---|
 | |
| 1-10. Linuche unguiculata 11. Linuche aquila (top centre) | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Cnidaria |
| Class: | Scyphozoa |
| Order: | Coronatae |
| Family: | Linuchidae |
| Genus: | Linuche |
| Species: | L. unguiculata |
| Binomial name | |
| Linuche unguiculata (Schwartz, 1788) | |
| Synonyms | |
|
Linuche draco (Haeckel, 1880)[1] | |
The thimble jellyfish (Linuche unguiculata) is a species of cnidarian found in the neotropical Atlantic Ocean.[2][3] It is a tiny jellyfish with a straight-sided, flat-topped bell. This jellyfish is the most common cause of seabather's eruption, a reaction caused by the injection of juvenile jellyfish nematocysts into human skin.[4]
Description
The medusa of the thimble jellyfish has straight sides with sixteen grooves, and a flat top. The coronal groove between the top and sides provides flexibility. The margin of the bell has sixteen lappets (folds), the niches between these bearing alternately rhopalia (sense organs) and short tentacles (eight of each). There is no marginal ring canal. Symbiotic zooxanthellae give the bell an overall orangish-brown colour and the translucent mesoglea has dark flecks. This jellyfish can reach a diameter of 16 mm (0.6 in) and a height of 20 mm (0.8 in).[1][5]
Distribution and habitat
The thimble jellyfish is found in the tropical and subtropical western Atlantic Ocean, particularly around the West Indies and the Bahamas. Although it can occur in warm surface waters, it has been found at depths down to about 5,000 m (16,000 ft). Its presence in any particular location is related to such factors as the presence of prey, temperature, salinity and oxygen saturation of the water.[5]
Ecology
The thimble jellyfish swims constantly by pulsating its bell, rotating as it moves. It forms swarms in warm seas near the surface of the water.[1] Aggregations have been reported covering a million square metres 1,000,000 m2 (1,200,000 sq yd). The jellyfish feeds on plankton, drawing a water current past its outstretched tentacles by pulsating the bell. When edible zooplankton are encountered, they are immobilised by the cnidocytes (stinging cells) and passed by the tentacles to the mouth on the underside of the bell. Thimble jellyfish are consumed by fish, sea turtles and other predators.[5]
Seabather's eruption
Larvae of the thimble jellyfish are the most common cause of seabather's eruption in the Caribbean and the Gulf of Mexico.[6] This is an itchy rash of small red papules that develops in the areas that were covered by the bather's swimwear or hair. The condition does not occur immediately, but after the bather has showered or the skin has dried, killing the jellyfish larvae which react by discharging their stinging cells. In Florida, most cases occur between March and August. A similar condition occurs on the east coast of North America after exposure to the larvae of the sea anemone Edwardsiella lineata.[6][7]
References
- 1 2 3 Schuchert, Peter (2018). "Linuche unguiculata (Schwartz, 1788)". World Register of Marine Species. Retrieved 23 May 2018.
- ↑ Calder, D. 2009. Cubozoan and Scyphozoan jellyfishes of the Carolinian biogeographic province, southeastern USA. Toronto, ON, Canada: Royal Ontario Museum.
- ↑ Fautin, D. 2004. Coelenterate Biology 2003: Trends in Research on Cnidaria and Ctenophora. The Netherlands: Kluwer Academic Publishers.
- ↑ Mayer, A. 1910. Medusae of the World; Volume III: The Scyphomedusae. Washington, D.C.: The Carnegie Institution of Washington.
- 1 2 3 DuBay, Mary Kay. "Linuche unguiculata: Thimble jellyfish". ADW. University of Michigan Museum of Zoology. Retrieved 23 May 2018.
- 1 2 Prohaska, Joseph; Tanner, Laura S. (15 February 2018). "Seabather's eruption". StatPearls. Retrieved 25 May 2018.
- ↑ Freudenthal, A.R.; Joseph, P.R. (1993). "Seabather's eruption". New England Journal of Medicine. 329 (8): 542–544. doi:10.1056/NEJM199308193290805. PMID 8336754.