(Fig. 5B)

Diagnosis. Argyropelecus aculeatus differs from congeners by the presence of denticles in the SC photophores; PAN, AN and SC in separated groups; two post-abdominal spines with different sizes, the posterior one markedly larger than the anterior; posteriormost abdominal keel scale slanting forward; dorsal blade height and width approximately equal; 9–10 dorsal-fin rays; lower jaw with a pair of canine teeth (Baird, 1971; Borodulina, 1978; Lima et al., 2011; Harold et al., 2015).

Geographical distribution. Circumglobal in tropical and temperate waters, between 43ºN and 40ºS (Baird, 1971; Parin et al., 1974; Borodulina, 1978; Pequeño, 1989; Quéro et al., 1990b; McAllister, 1990; Harold, 2003; Harold et al., 2015; Sutton et al., 2020; Love et al., 2021). In the western Atlantic, the species was reported from off the United States to Uruguay, including the Gulf of Mexico and the Caribbean Sea (McEachran, Fechhelm, 1998; Harold, 2003; Moore et al., 2003; Judkins, Haedrich, 2018; Ramírez et al., 2019). In the Brazilian EEZ, A. aculeatus was previously reported from off the northeast to southeast coast, including the Rocas Atoll and the Fernando de Noronha and Saint Peter and Saint Paul archipelagos (Borodulina, 1978; Figueiredo et al., 2002; Menezes et al., 2003; Bernardes et al., 2005; Braga et al., 2007; Haimovici et al., 2008; Costa, Mincarone, 2010; Lima et al., 2011; Judkins, Haedrich, 2018; Eduardo et al., 2018a, 2020a). Larvae were also recorded off Rio de Janeiro State (Bonecker et al., 2014). Specimens of A. aculeatus examined here were collected off Rio Grande do Norte (including seamounts), Paraíba, and Pernambuco States, in addition to the Rocas Atoll and Fernando de Noronha Archipelago, between depths of 430 and 1,113 m (Fig. 3D).

Specimens examined. 43 (30–82 mm SL): NPM 4112, 6 (32–46 mm), AB2#16; NPM 4113, 1 (46 mm), AB2#39; NPM 4114, 1 (45 mm), AB2#60B; NPM 4120, 1 (42 mm), AB2#59A; NPM 4125, 1 (48 mm), AB2#52B; NPM 4131, 22 (34–82 mm), AB2#58A; NPM 4133, 1 (82 mm), AB2#41A; NPM 4142, 1 (36 mm), AB2#21; NPM 4187, 9 (30–67 mm), AB2#56C.