Typically Arctic species, extending its range from the Arctic Basin into adjoining seas. Is more numerous in the North Pacific than in the North Atlantic. Does not extend farther south than the south coast of Greenland.
Cold-water species (ranges in waters from -1.8*C to 8-10*C). Maximum abundance is observed in waters of temperatures -1.8 - +1*C
Reproduction occurs in surface waters, as well as the early development of nauplii and early copepodites. Starting with C4-C5 start performing diel vertical migrations and seasonal ontogenetic migrations. Overwinter at depth in a state of diapause, are almost absent from the surface layers in the winter months.
Female:
The ventral surface of the genital segment from lateral view curves immediately posteriad of the genital pore. The genital structures are very similar to that of C. finmarchicus and C. marshallae. The genital plate is smoothly curved in its posterior part and cut-off in the anterior, covering the proximal part of the chitinized seminal receptacles, which are slightly tilted toward the long axis of the body. The posterior corners of the last thoracic segment are always rounded. The serrated line on the coxopodite of C5 is very dense and more curved than in C. finmarchicus. The medial line of the 2nd segment of the basipodite of P5 is less curved than in C. finmarchicus. The spiniform process on the distal front edge of the P5 basipodite is usually wide and obtuse. The distal corner of the 1st segment of the endopodite is thicker and more dull than in M. finmarchicus. The inner edge of the 1st endopodal segment of P1 carries 1 seta, the inner and outer edges of the 3rd endopodal segment of P5 carry 3 setae. The photoreceptory glands are placed away from the lateral gland.
Male:
The P5 has an almost equal number of setae on the right and left branch. The outer distal process on the 2nd endopodal segment of the left P5 does not usually reach the distal edge of the 1st exopodal segment of this leg.
Filter-feeders, feed on various components of the phytoplankton, primarily diatoms
