Obelia longissima (Pallas, 1766)

Material examined: BBB 2016: St. 23; St. 35; St. 38.

Distribution: Cosmopolitan. In the southwestern Atlantic it was reported from 34°S to 55°S (Oliveira et al. 2016). This is the first record of an Obelia species in MPA Namuncurá I.

Remarks: Synonyms at the area are Laomedea (Obelia) longissima (Vervoort 1972); Obelia gracilis (Milstein 1976) . Several colonies without gonothecae were assigned to this species. Cornelius (1975) synonymized Obelia longissima with O. dichotoma but, later on, Cornelius (1995) considered both species as valid. However, considering that some geographical records in the literature of these species are still confusing, further studies are necessary in order to confirm their validity or adopt any synonymy.