A new notodelphyid copepod, Doropygopsis arctica sp. nov. (Cyclopoida), parasitic in ascidian of the Molgula arctica from the White Sea

Doropygopsis arctica, a new species of notodelphyid cyclopoid from the branchial cavity of Molgula arctica Kiaer, 1896 (Ascidiacea) in Chupa Bay (Kandalakshskiy Zaliv, White Sea) is described. The new species differs from the two other congeners by the fine structure of some cephalosomic appendages and swimming legs. The diagnosis for Doropygopsis is redefined.