Gaetanus paracurvicornis is an aetideid calanoid copepod known after female (4.60-5.10 mm in length) from the Pacific Ocean, Antarctic and the northern part of the Atlantic Ocean, mainly bathy-abyssopelagic.
Female. Total length 4.60-5.10 mm. Cephalothorax 4.5-5.5 times longer than abdomen. Frontal spine present, robust, directed forward in its base, its top curved to rostrum. Spines on Th5 posterior corners arranged in the middle of lateral border (lateral view), straight, reaching about the midlength of genital segment. A1 by 3 last segments longer than body. Re1 A2 with 1, Re2 A2 with 2 setae. Md palp base with 2, Ri1 Md with 2, Ri2 Md with 9 terminal setae and 1 posterior seta. Second internal Mx1 lobe with 5, Ri with 15 setae. Lateral plate on Mxp protopodite absent, but in some specimens traces of the plate are visible. P1 with 3-segmented Re subdivision of Re2 and Re3 incomplete, external spines on Re2 and Re3 present. Ri P2 2-segmented. P4 coxopodite with about 30 thin spines.
Abysso-, bathypelagic species, found in hauls between 3000 and 5000 m (Markhaseva, 1996).
In the northern part of the Pacific Ocean in regions of the Kurile-Kamchatka and Aleutian Trenches; in the south-eastern part of the Pacific Ocean near the coast of Chili, in the Indo-oceanic sector of Antarctic to the South from 62°S and in the North Atlantic (Markhaseva, 1996).
Type locality: the Kurile-Kamchatka Trench region (Brodsky, 1950).
42 females from samples: 68, 85, 97, 98, 139, 147, 193, 379, 444, 447, 456. See examined samples module.
Lectotype: 1 female of fifth copepodid stage N 39806, high latitude expedition of Arctic Scientific Institution, 25 July 1946; ice-breaker "Severny Polus"; depth of site 4600 m, stratum of sampling: 4000-0 m. Kept in the Zoological Institute, Russian Academy of Sciences, St. Petersburg.