TL;DR: Five new species are described in detail with differential diagnoses provided, and identification keys for the genera Sagitta, Parasagitta, and Pseudosagitta are given.
Abstract: Sagittidae species from the Arctic Seas of Russia and adjacent water bodies are listed. Diagnoses for the subclass Sagittiones Kassatkina 2011, order Aphragmophora Tokioka 1965, and family Sagittidae Claus et Groben 1905 are given. Five new species are described in detail with differential diagnoses provided, and identification keys for the genera Sagitta, Parasagitta, and Pseudosagitta are given. The study is illustrated by drawings and photographs.