Benthic Harpacticoida of the Kara Sea: Species Composition and Bathymetrically Related Distribution

Abstract

Data on benthic harpacticoid copepods from the Voronin Trench (central part of the Kara Sea) are reported for the first time. Harpacticoids accounted for 1–25% of total meiofauna, their abundance varied from 6 to 102 ind./10 cm2 and decreased with depth. I total, 42 nominal species have been found, 15 species are new for the Kara Sea, and at least 8 species are new for science. Several species have been recorded for Arctic waters for the first time: Cylindronannopus bispinosus, Haloschizopera clotensis, H. bathyalis, Metauntemannia pseudomagniceps, Mesocletdemus duosetosus, M. parabodini, Proameira echinipes, and Cletodes tuberculatus. The most species-rich families are Ameiridae, Argestidae, Pseudotachidiidae, Miraciidae, and Ectinosomatidae. Comparative analysis including the data obtained at shallow-water stations from the Yenisei Gulf (southern Kara Sea) revealed three assemblages occupying different habitats. The assemblage inhabiting shallow-water silts (20–62-m depth) was the poorest in regard to species diversity; shallow-water sands were richer in species number, while the deepest stations (92–698 m) were the richest. The latter assemblage had the composition of families typical for the deep-sea areas. The fauna of the Kara Sea includes by now 82 harpacticoid species, most of which have been also reported from North Atlantic and/or western Arctic waters.