Markhaseva, 1996
Short Description:
Chiridiella reductella is an aetideid calanoid copepod known after female (2.40-3.10 mm). Species recorded in Arctic Basin in meso- and bathypelagic waters.
Taxonomic Description:
Female. Total length 2.40-3.10 mm. Cephalothorax 3 times longer than abdomen. Anterior part of skeleton structures of genital field wavy (lateral view). A1 23-segmented, shorter than cephalothorax. Re A2 1.7 times longer than Ri. A2 right Re5-Re6 with group of minute spinules. Mx1 gnathobase with 10 setae, Ri with 3, Re with 1 seta, external lobe with 8 setae (second and third lobes were not visible, very possible they reduced). Mx2 with completely reduced first and naked second endite, third endite with 1 long seta, distal part of Ri absent, even the setae on the fifth endite absent. The distal part of Mxp protopodite with 1 seta, Ri1 Mxp with 2 medial setae. Re P1 with 1 small terminal spine. Re1 P2 and Re1 P3 without external spines, these rami are 3-segmented (P2 unclearly 3-segmented). Ri P2-P4 one-segmented.
Male unknown.
Remarks. Brodsky (1950) described Ch. reducta after male and female. Female from the type series of Ch. reducta was lost, according to Brodsky's (1950) figures is identical to the above species. Male is kept in the collections of the Zoological Institute, St. Petersburg, designated as lectotype actually exists and should be attributed to Ch. abyssalis . Therefore the name Ch. reducta is synonymized with Ch. abyssalis (Markhaseva, 1996).
Vertical distribution:
The species was found in hauls 400-1000 m, in total hauls from 2000 m (Brodsky, 1950) and in haul 250-900 m (Markhaseva, 1996).
Geographical distribution:
Arctic Basin: the central part (Brodsky, 1950; Markhaseva, 1996).
Type locality: 82°28'N 167°38'E.
Material examined:
1 female from sample 521. See examined samples module.
Holotype, 1 female, N 1/64822, 82°28'N 167°38'E, "SP-17", Sta 1, 24 June 1968, in haul 250-900 m.