A new species of the genus Chaetozone (Annelida: Cirratulidae) from the seaward part of Chaunskaya Bay in the East Siberian Sea (Russia)
S.Yu. Gagaev 
Abstract. Based on material collected by the author over several years and seasons in Chaunskaya Bay of the East Siberian Sea, a new species, Chaetozone buzhinskajae sp. nov., is described. Morphologically, it is most similar to Ch. setosa Malmgren, 1867 and Ch. pugettensis Blake, 2015, which belong to a group of species characterised by an enlarged lobe or crest covering the peristomium. The new species is distinguished by the presence of neuropodial spines in the anterior part of the last third of the body (from the 48th to the 72nd setigerous segment), a complete achaetous segment that is well separated from the peristomium and setiger 1, and a distinctive methylene green staining pattern. Specimens were collected at depths ranging from 12 to 50 m in the seaward part of the bay.
Key words: benthos, East Arctic, taxonomy, Polychaeta, Cirratulidae, Chaetozone, new species
Zoosystematica Rossica, 2024, 33(2): 237–243 ▪ Published online 2 October 2024
https://doi.org/10.31610/zsr/2024.33.2.237 ▪ Open full article 
References
Blake J.A. 1996. Chapter 8. Family Cirratulidae Ryckholdt, 1851. In: Blake J.A., Hilbig B. & Scott P.H. (Eds). Taxonomic atlas of the Santa Maria Basin and Western Santa Barbara Channel, 6.Annelida. Part 3. Polychaeta: Orbiniidae to Cossuridae: 263–384. Santa Barbara Museum of Natural History.
Blake J.A. 2006. New species and records of deep-water Cirratulidae (Polychaeta) from off Northern California. Scientia Marina, 70 (Supplement 3): 45–57. https://doi.org/10.3989/scimar.2006.70s345
Blake J.A. 2015. New species of Chaetozone and Tharyx (Polychaeta: Cirratulidae) from the Alaskan and Canadian Arctic and the Northeastern Pacific, including a description of the lectotype of Chaetozone setosa Malmgren from Spitsbergen in the Norwegian Arctic. Zootaxa, 3919(3): 501–552. https://doi.org/10.11646/zootaxa.3919.3.5
Buzhinskaja G.N. 2001. Class Polychaeta. In: Sirenko B.I. (Ed.). Explorations of the fauna of the seas, 51. List of species of free living invertebrates of Eurasian Arctic seas and adjacent deep waters: 52–66. St Petersburg: ZIN.
Chambers S.J. 2000. A redescription of Chaetozone setosa Malmgren, 1867 including a definition of the genus, and a description of a new species of Chaetozone (Polychaeta: Cirratulidae) from the northeast Atlantic. Bulletin of marine Science, 67(1): 587–596.
Chambers S.J. & Woodham A. 2003. A new species of Chaetozone (Polychaeta: Cirratulidae) from deep water in the northeast Atlantic, with comments on the diversity of the genus in cold northern waters. Hydrobiologia, 496(1–3): 41–48. https://doi.org/10.1023/a:1026116008735
Gagaev S.Yu. 1987. On the issue of the hydrobiological regime of Chaunskaya Bay of the East Siberian Sea. Oceanologiya, 27(4): 649–651. (In Russian).
Gagaev S.Yu. 1994. Polychaetes of Chaunskaya Bay and their role in its ecosystems. In: Scarlato O.A. (Ed.). Issledovaniya fauny morey [Explorations of the fauna of the seas], 47: 148–177. (In Russian). St Petersburg: ZIN.
Gagaev S.Yu. 2004. Growth and bioenergetic characteristics of polychaete populations from Chaunskaya Bay of the East Siberian Sea. Oceanologiya, 44(3): 415–419. (In Russian).
Gagaev S.Yu. 2010. Fauna of polychaete worms (Polychaeta) of the East Siberian Sea and their biogeographic characteristics. In: Sirenko B.I. & Denisenko S.G. (Eds). Issledovaniya fauny morey [Explorations of the fauna of the seas], 63: 8–40. (In Russian).
Golikov A.N., Gagaev S.Yu., Galtsova V.V., Golikov A.A., Dunton K., Menshutkina T.V., Novikov O.K., Petrjashev V.V., Potin V.V., Sirenko B.I., Schonberg S. & Vladimirov M.V. 1994. Ecosystems of Chaunskaya Bay of the East Siberian Sea. In: Scarlato O.A. (Ed.). Issledovaniya fauny morey [Explorations of the fauna of the seas], 47: 4–111. (In Russian).
Grosse M., Capa M. & Bakken T. 2021. Describing the hidden species diversity of Chaetozone(Annelida, Cirratulidae) in the Norwegian Sea using morphological and molecular diagnostics. ZooKeys, 1039: 139–176. https://doi.org/10.3897/zookeys.1039.61098
Jirkov I.A. 2001. Polikhety Severnogo Ledovitogo okeana [Polychaetes of the Arctic Ocean]. Moscow: Yakus-K. 632 p. (In Russian).
Malmgren A.J. 1867. Annulata Polychaeta Spetsbergiae, Groenlandiae, Islandiae et Scandinaviae hactenus cognita. Öfversigt af Kongliga Vetenskaps-Akademiens förhandlingar, 24: 127–235. https://doi.org/10.5962/bhl.title.13358
McIntosh W.C. 1911. XVI – Notes from the Gatty Marine Laboratory, St. Andrews. No. 32. Annals and Magazine of natural History(Eight Series), 7(38): 145–173. https://doi.org/10.1080/00222931108692919
Woodham A. & Chambers S. 1994. A new species of Chaetozone (Polychaeta, Cirratulidae) from Europe, with a re-description of Caulleriella zetlandica (McIntosh).Mémoires du Muséum national d’Histoire naturelle, 162: 307-316.
Read G. & Fauchald K. (Eds). 2024. Nephtyidae Grube, 1850. World Polychaeta database. World Register of Marine Species [online]. https://www.marinespecies.org/aphia.php?p=taxdetails&id=956 [updated 26 March 2008; viewed 1 March 2024].