Lubbock, 1856
Short Description:
Undeuchaeta plumosa is an aetideid calanoid copepod known after both sexes (female 3.00-4.20 mm and male 2.85-3.90 mm in length) from the Atlantic, Pacific and Indian oceans, of mostly meso- and sometimes epipelagic.
Taxonomic Description:
Female. Total length 3.00-4.20 mm. Cephalothorax about 3-4 times longer than abdomen. Crest absent. Th5 posterior corners asymmetrical: in lateral view the right one rounded, the left obtuse-triangular. Their configuration may vary. Genital segment asymmetrical due to presence of spine on the right side. A1 nearly as long as cephalothorax, or reaching Abd3. Re1 A2 without setae. Mxp protopodite with 5 setae near Ri base, Ri with 15 setae. Oral parts and P1-P4 typical of the genus.
Male. Total length 2.85-3.90 mm. Segmentation of body as in female. Crest absent. Th5 posterior corners rounded. Cephalothorax about 3 times longer than abdomen. A1 reaching the end of cephalothorax, or Abd2. Oral parts reduced in comparison with that in female, P1-P5 typical of the genus.
Vertical distribution:
Most probably the main zone of inhabitance is mesopelagic, but species often occurs in epipelagic as well (Scott. A, 1909; Mori, 1937; Grice, 1962; Tanaka and Omori, 1970b; Vervoort, 1963; Morris, 1970; Bradford and Jillett, 1980).
Geographical distribution:
Widespread in the Atlantic Ocean in the North to 62°N (Jespersen, 1940), to the South to 35°S (Wolfenden, 1911). Also widespread in the Indian and Pacific Oceans. In the Pacific Ocean; the northernmost locality is the Sea of Okhotsk about 49°N (Markhaseva, 1996), the southernmost about 52°S (Farran, 1929).
Type locality: the Atlantic Ocean (Lubbock, 1856).
Material examined:
More than 70 females and 6 males from samples: 49, 51, 201, 202, 390, 391, 394, 400, 437, 439, 456, 457. See examined samples module.