Arctokonstantinus hardingi is based on a female specimen collected at bathypelagic depths in the Arctic Ocean. The new family has similarities with the family Spinocalanidae (superfamily Spinocalanoidea); however, it does not fit well the diagnosis of the superfamily and family in length of antennule, setation of mandible and maxillule, significantly deviating morphology of maxilla and maxilliped and segmentation of P I exopod. Probably the new family represents a new calanoid superfamily; however, until the male is known the species it is tentatively placed into the superfamily Spinocalanoidea. Arctokonstantinidae is attributed to the Spinocalanoidea based on segmentation and setation pattern of swimming legs P2-P4 and antennule structure. Relying on mouth-part morphology Arctokonstantinus could be considered a predator.