Neritic Jellyfishes ( Cnidaria : Cubozoa and Scyphozoa ) from the coast of Rio Grande do Norte state , northeast of Brazil

For the entire Brazilian coast, there are 22 published records of scyphozoans. On the other hand, only 35 species of cubozoans were described worldwide, four of them reported for the Brazilian coast. However, little is known about the species of cubozoans and scyphozoans in the Northeastern states of Brazil. The aim of this study was to perform a survey of the jellyfish (Cnidaria: Cubozoa and Scyphozoa) on the coast of Rio Grande do Norte state, Northeast of Brazil. Specimens were collected using trawl net on beaches in the counties of Natal (in 2003) and Tibaú (in 2004). For the Rio Grande do Norte coast there were few records of large jellyfish, and new records of the following cubozoan and scyphozoan species were verified: Chiropsalmus quadrumanus; Chrysaora lactea; Lychnorhiza lucerna and Stomolophus meleagris. The studied species had their distributions expanded in the coast to the State of Rio Grande do Norte.


Introduction
Cubozoa and Scyphozoa, both classes of Cnidaria, are composed mainly by large solitary marine invertebrates (Mianzan and Cornelius 1999).In these classes, the pelagic stage as a jellyfish is more conspicuous in the life cycle, while the polypoid form is restricted to a small sessile stage (Arai 1997).Currently, there are ca.200 species in the Class Scyphozoa (distributed in 19 families and 50 genera), all of them exclusively marine (Kramp 1961;Mianzan and Cornelius 1999).Class Cubozoa constitutes a group with about 35 species, the jellyfishes having an umbrella with cubical outlines.
Studies concerning biogeography of jellyfishes are scarce, especially for the South Atlantic (Mianzan and Cornelius 1999;Segura-Puertas et al. 2003;Altuna 2008).Gershwin (2001) remarked that the confusing systematics of these animals contributes to this scarcity.Color differences, pigmentation patterns and slight anatomical variations guided the nominal description of species during the nineteenth century (Kramp 1961).
In the South Atlantic, Mianzan and Cornelius (1999), in a wide literature revision, listed 34 species of scyphozoans and 5 of cubozoans.For the entire Brazilian coast, there are 22 records of scyphozoans (Migotto et al. 2002;Marques et al. 2003).On the other hand, only about 35 species of cubozoans were described worldwide, four of them reported for the Brazilian coast (Migotto et al. 2002;Morandini 2003).Marques et al. (2003) discussed the knowledge on Medusozoa (Cubozoa, Hydrozoa, Scyphozoa and Staurozoa) under a geographical and historical perspective for the Brazilian coast.A lack of knowledge was observed for some areas, where more studies should focus.The Northeast region of Brazil is the least known area in all biological aspects concerning medusozoans but Neumann-Leitão et al. (2008) recently reported the scyphozoan Aurelia sp. in state of Rio Grande do Norte.
The present contribution presents a preliminary survey on Scyphozoa and Cubozoa (Cnidaria: Medusozoa) of coastal waters in Rio Grande do Norte, increasing the knowledge on this group for the Northeastern states.

Material and methods
The material was collected on the coast of the state of Rio Grande do Norte, performed together with the fishermen of Natal beach (05°44'59.73" S, 35° 12'11.78" W), in 2003, and Tibaú beach (04º53'20.12" S, 37°13'26.77" W), in 2004, by trawl net.Large jellyfishes were submitted to fixation (using a solution of 4% formaldehyde in seawater) and later identified in Laboratory of Marine Invertebrates, Universidade Federal do Ceará (UFC).
Remarks: Distribution comprehends Jamaica and the Atlantic coast of South America.Chrysaora lactea and C. quinquecirrha occur on the Atlantic coast of America; C. lactea occurs more to the South of the continent and C. quinquecirrha more to the North.Morandini et al. (2004) described the life cycle of the species C. lactea, which displays differences in the stages of development to other known life cycles of Chrysaora species.Morandini et al. (2006b) redescribed the species based on specimens from the South Atlantic and designating a neotype.
Remarks: Its distribution comprehends both Atlantic and Pacific coasts of America.Calder (1982;1983) described its life cycle in laboratory and made remarks on the nematocysts during different life stages.Bigelow (1914) recognized that all species of the genus should be synonymized with S. meleagris.Specimens from the Northern shores of South America were considered a distinct variety (Stomolophus meleagris fritillaria) (Kramp 1955).
Chiropsalmus quadrumanus, Chrysaora lactea, Lychnorhiza lucerna and Stomolophus meleagris are recorded for the first time to the state of Rio Grande do Norte, expanding the range of these species in Brazil and filling some gaps on the distribution in the Tropical South Atlantic as well.