Species richness and the level of knowledge of the bryozoan fauna of the Arctic region

N.V. Denisenko

Proceedings of the Zoological Institute RAS, 2020, 324(3): 353–363 · https://doi.org/10.31610/trudyzin/2020.324.3.353

Full text

Abstract

The publication presents the results of the analysis of retrospective data and samples of bryozoans collected in different seas and areas of the Arctic region during recent 30 years. To date, 518 species of bryozoans have been recorded in the Arctic, which is on 26.4% more than previously registered. The level of increase in species numbers in the species lists of the regional faunas was different in different areas. In the waters of Greenland, the found species diversity of bryozoans was on 12% higher; in the Barents and Kara Seas – on 18 and 19%, respectively; in the Laptev and East Siberian seas – on 30%; in the Faroe Islands waters on 30% than it was previously marked. In the Icelandic waters and the Chukchi Sea, the number of bryozoan species is richer by five and two times respectively than it was considered earlier. Our assessment of the modern knowledge of the fauna of this group using the method of rarefaction showed that the bryozoan fauna is still underexplored. The Chao metric calculations also indicate that expected species richness would increase by 10–30% in different areas of the Arctic in case of additional sampling efforts. At the same time, a measure of taxonomic distinguish of the fauna allows to conclude that the species composition of bryozoans has already been sufficiently studied in most of the considered areas of the Arctic zone except in the waters of the Canadian Arctic Archipelago.

Key words

Arctic, bryozoans, species richness, state of knowledge

Submitted March 11, 2020 · Accepted August 28, 2020 · Published September 25, 2020

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