Farran, 1905
Short Description:
Gaetanus minor is an aetideid calanoid copepod known after female (1.7-2.40 mm in length) from tropical parts of all oceans and some other localities in epi- and meso-bathypelagic.
Taxonomic Description:
Female. Total length 1.70-2.40 mm. Cephalothorax about 4 times longer than abdomen. Frontal spine present, curved to rostrum. Spines on Th5 posterior corners covering about three fourth of genital segment length, they are straight and removed to the back side of specimen (lateral view). A1 of about the same length as body. Re1 A2 lacking setae, Re2 A2 with 2 setae. Md palp base with 2 setae, Ri1 Md with 1, Ri2 with 9 terminal setae. Second Mx1 internal lobe with 4 setae, Ri with 13 (?) setae. Mxp protopodite with lateral plate. Re P1 2-segmented, each segment with 1 external spine. Ri P2 one-segmented. P4 coxopodite with 12-15 spines.
Male unknown.
Vertical distribution:
The species was found in hauls from meso-, bathypelagic, rarely from epipelagic (Farran, 1905, 1929; With, 1915; Bradford and Jillett, 1980) and from total hauls from depths 500-7000 m.
Geographical distribution:
The northernmost distribution: in the Atlantic Ocean to the south-west of Iceland (Jespersen, 1934), the southernmost: region of 32°S (Wolfenden, 1911); found in the Arabian Sea and the Bay of Bengal (Sewell, 1929, 1947), the southernmost locality in the Indian Ocean in the region of 27°N (Grice and Hulsemann, 1967); in the Pacific Ocean the northernmost finding: the Izu region (Tanaka, 1957b), the southernmost region of 49°S (Park, 1978). Species known from tropical waters in all oceans.
Type locality: the Atlantic Ireland Slope (Farran, 1905).
Material examined:
16 females from samples: 46, 49, 50, 52, 53, 201, 202, 400, 413, 416, 420, 443, 456, 457, 573. See examined samples module.