First occurrence of the genus <i>Pandeopsis</i> (Hydrozoa: Anthoathecata) in the South Atlantic Ocean

Abstract A specimen of the genus Pandeopsis Kramp, 1959 was found in surface waters off the northeast Brazilian coast at 10.93°S, 36.48°W. The specimen was assigned to the family Pandeidae on the basis of the presence of more than four hollow marginal tentacles and the absence of divided radial canals, marginal tentacles with terminal cnidocyst cluster, and oral tentacles. Among Pandeidae, the specimen was assigned to Pandeopsis due to the absence of lateral diverticula, centripetal canals, and marginal cirri as well as the presence of more than two marginal tentacles, mesenteries, smooth gonads, and manubrium with a quadrangular base. To the moment, the unique morphological trait that is likely to distinguish the two species of the genus is the presence of medusa buds in the gonads of Pandeopsis prolifera , which was not present in the specimen we found. However, as this is not a strong trait to distinguish species, we consider the present specimen to be Pandeopsis cf. ikarii . This study represents the first record of the genus in the South Atlantic Ocean.