New species of Eirenidae (Hydrozoa: Leptothecata) from the Amazonian coast (northern Brazil)




jellyfish, Cnidaria, Hydrozoa, taxonomy, biodiversity, Atlantic Ocean, new species


Two new Eirenidae medusae species were collected on the Amazonian coast, Eutima marajoara n. sp. and Helgicirrha angelicae n. sp. The former differs from other species of the genus by the gonads extending along almost the entire length of the subumbrellar portion of the radial canals but not connected to the ring canal, up to 40 marginal tentacles with conical bulbs and 48 marginal warts, lateral cirri and adaxial papillae on some marginal warts and tentacular bulbs. Helgicirrha angelicae n. sp. differs from other species of the genus by the gonads on the middle portion of the radial canals with medusa buds, the short gastric peduncle, up to 20 marginal tentacles, some with adaxial papillae, up to three marginal warts and two statocysts between successive tentacles, and lateral cirri both on tentacle bulbs and marginal warts.


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How to Cite

Giachini Tosetto E, Neumann-Leitão S, Nogueira Júnior M. New species of Eirenidae (Hydrozoa: Leptothecata) from the Amazonian coast (northern Brazil). scimar [Internet]. 2020Dec.11 [cited 2021Apr.22];84(4):421-30. Available from: