Lubbock, 1856
Short Description:
Euchirella pulchra is an aetideid calanoid copepod known after both sexes (female 3.04-4.40 and male 3.06-4.15 mm in length) widespread in tropical, subtropical and temperate zones of the World Ocean in epipelagic, meso- and bathypelagic.
Taxonomic Description:
Female. Total length 3.04-4.40 mm. Cephalothorax about 4 times longer than abdomen. Crest absent. Anterior part of cephalon (laterally) rounded or slightly triangular. Rostrum well developed. Genital segment asymmetrical with large "ear-like" swelling on the left side and small depression on the right. Th5 posterior corners symmetrical, rounded. A1 reaching nearly the end of genital segment, or Abd3. Ri A2 nearly 3 times shorter than Re A2, coxo- and basipodite A2 with 1 seta each, both lobes of Ri2 A2 with 6 setae. On the second and third internal lobes of Mx1 are 1 and 2 setae respectively, on protopodite near the Ri base 3 setae, on Ri 4 setae, on Re 11 and on external lobe 6 setae. Mxp protopodite in comparison with that of E. pseudopulchra with 1 seta in the proximal part of the segment (Von Vaupel Klein, 1984); other oral parts and P1-P4 typical of the genus. P4 coxopodite with 2 spines.
Male. (Description after Park (1976a) with modifications). Total length 3.06-4.15 mm. Cephalon with low crest. Rostrum well developed. Left P5 without Ri, Re1 not reaching the distal end of right basipodite. Ri P5 right with 4 projections along external border; 3 projections visible on Re1.
Vertical distribution:
The species was found in epipelagic (Vervoort, 1949; 1963; Sewell, 1947; Grice, 1962; Von Vaupel Klein, 1984) and it was also recorded at night in the Gulf of Mexico. In the daytime, however, high densities were recorded between 500 and 1000 m. The deepest occurrence was 2000 m (Park, 1976b). The species was found in total hauls from 800-1000 m (Tanaka and Omori, 1969a).
Geographical distribution:
Widespread in the tropical, subtropical and temperate zones of the World Ocean.
Type locality: Tropical Atlantic (Lubbock, 1856).
Material examined:
3 females from samples 419, 573. See examined samples module.