ИСТИНА

Pelagic polychaetes collected in the deep Eurasian Basin (Arctic Ocean) during the RV “Polarstern” cruises PS95 (September-October 2015) and PS101 (September-October 2016) were investigated morphologically and using the molecular analysis of mitochondrial 16S and nuclear 18 and 28S gene sequences. Two holoplanktonic species (Pelagobia longicirrata, Fam. Lopadorrynchidae and Typhloscolex muelleri, Fam. Typhloscolecidae), common for the Arctic Ocean, were identified in the studied collections. Both of them were collected in the upper mesopelagic, from the depths 0—800 m. Phalacrophorus pictus borealis, Fam. Iospilidae, was collected from the depths 0—4000 m. Basing both on morphological and molecular data, we suppose the validity of P. borealis, previously synonymized with P. pictus. Along with them we found two new species. The first of them belongs to the genus Pelagobia; it was collected from the bathypelagic layer 3000—3860 m. The second one was also collected from the bathypelagic depths (2000—4830 m) and belongs to genus Bathypolaria, Fam. Polynoidae. The morphological description of the new Polychaeta species found during our studies supplied with molecular data will help to produce more comprehensive species inventory and reference DNA database for Arctic Ocean biodiversity.