Figure 13. Hesperodiaptomus arcticus Marsh. Male. (a-b) 5th legs, posterior view, (a) (redrawn after Wilson 1959); (b) Clearwater L., B.C.; (c) detail of left 5th leg, exopod 2, posterior view; Clearwater L., B.C.; (d-e) right 1st antenna with antennal process on segment 23; (d) Clearwater L., B.C.; (e) (after Rylov 1922)