Marine Species Identification Portal : Pseudochirella notacantha

Sars, 1905

Short Description:

Pseudochirella notacantha is an aetideid calanoid copepod known after both sexes (female 5.45-6.80 mm and male 4.90-5.80 mm in length) from the Atlantic, Pacific and Indian oceans, mainly meso-bathypelagic.

Taxonomic Description:

Female. Total length 5.45-6.80 mm. Cephalothorax 3.7-4.2 times longer than abdomen. Th5 posterior corners symmetrical, rounded. Genital segment asymmetrical, with moderate knob-like projections on the left and on the right, their shape varying. Abd1-3 covered with hairs. A1 as long as cephalothorax, or reaching caudal rami. Re1 A2 with 1 very small seta, Re2 A2 with 1 distal seta, Ri1 A2 with 2, Ri1 Md with 2 (?3), Ri2 Md with 9 long terminal and 2 posterior setae. Mx1, Mx2 and Mxp typical of the genus. Re P1 indistinctly 3-segmented. Ri P2 indistinctly 2-segmented. P4 coxopodite with 6-9 spines.

Male. Total length 4.90-5.80 mm. Cephalon and Th1, as well as Th4-Th5 fused (Sars (1925) recorded the separation of segments). Th5 posterior corners with spines. Cephalothorax about 3 times longer than abdomen. Oral parts in comparison with that in female reduced. Re1 P1 with very small external spine. Ri P2 virtually 2-segmented. Spines on P4 coxopodite absent. Re2 P5 with 3 teeth in distal part of segment; Re3 P5 with rounded top.

Vertical distribution:

Meso-bathypelagic species, in the north-western Atlantic more often found in hauls between 400 and 1000 m, but also recorded in such hauls: 0-200, 200-300, 300-400 and 1425-1839 m (Ferrari, 1980), known of hauls 350-1710 m (Grice and Hulsemann, 1967), in haul from 300 m (Bjornberg, 1973) and also from total hauls from depths 1000-3000 m (Sars, 1925; Bjornberg, 1973; Markhaseva, 1996).

Geographical distribution:

Atlantic Ocean: to the North to 62°N (With, 1915; Jespersen, 1934), in the northern part of the Pacific Ocean was not found; the southernmost findings near 62-71°S (Hardy and Gunther, 1935; Farran, 1929; Park, 1978; Markhaseva, 1996), more often occurs in the North Atlantic and south-eastern part of the Pacific Ocean (Bjornberg, 1973; Sars, 1925; Deevey and Brooks, 1977; Ferrari, 1980; Markhaseva, 1996), also in the south-western part of the Pacific Ocean (Bradford and Jillett, 1980), in the Indian Ocean (Sewell, 1947; Grice and Hulsemann, 1967; Markhaseva, 1996).

Type locality: North-eastern Atlantic (Sars, 1905).

Material examined:

58 females and 6 males from samples: 266, 313, 353, 355-360, 362-369, 371, 375, 419, 571. See examined samples module.

Pseudochirella notacantha