Corymorpha januarii Steenstrup, 1855

Synonyms in the area: Amalthea ? Hybocodon ? januarii —Mayer 1910 [medusa]; Amalthea ? januarii —Vannucci 1951a [medusa]; Corymorpha sp. Migotto & Silveira, 1987 [polyp]; Hybocodon unicus —Zamponi & Facal 1987; Genzano et al. 2009a [non Hybocodon unicus (Browne, 1902)] [polyp].

Remarks: Vannucci (1951a) recorded Amalthea ? januarii (Steenstrup, 1854) for the region extended between Ilha Grande and Cabo Frio (Brazil), based on the record of Amalthea ? Hybocodon ? januarii from Mayer (1910a) for Rio de Janeiro State. Migotto & Silveira (1987) recorded Corymorpha sp. for Ubatuba, subsequently reidentified as Corymorpha januarii Steenstrup, 1854 (Silveira & Migotto 1992) .

Distribution in South America: polyp—Atlantic Ocean, Brazil to Argentina, from 22°S to 42.64°S (Steenstrup 1854; Vannucci 1951b; Mayer 1910; Migotto & Silveira 1987; Silveira & Migotto 1992; Migotto et al. 2002; Genzano et al. 2009a, 2009b; Silveira & Morandini 2011; Miranda et al. 2015);

medusa—Atlantic Ocean, Brazil to Argentina, from 23°S to 24°S, from 27°S to 28°S, from 37°S to 42.5°S (Vannucci 1951b; Silveira & Migotto 1992; Tronolone 2001; Migotto et al. 2002; Genzano et al. 2009b; Nogueira Jr. 2012; Guerrero et al. 2013; Nogueira Jr. et al. 2015a).

Habitat: endemic to the southwestern Atlantic Ocean; polyp—with digging behavior, with basal part embedded in soft bottoms in shallow waters, up to 25m depth;

medusa—planktonic medusae with ephemeral life, rarely sampled in plankton tows. (Migotto & Silveira 1987; Silveira & Migotto 1992; Genzano et al. 2009a).