A review of the genus Muusoctopus (Cephalopoda: Octopoda) from Arctic waters

• Published in: Zoological Letters
• Main Authors: Golikov, Alexey V., Gudmundsson, Gudmundur, Blicher, Martin E., Jørgensen, Lis Lindal, Korneeva, Ekaterina I., Olafsdottir, Steinunn H., Shagimardanova, Elena I., Shigapova, Leyla H., Zakharov, Denis V., Zimina, Olga L., Sabirov, Rushan M.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2023
• Subjects: Arctic; North Atlantic
• Online Access: https://hdl.handle.net/11250/3106813; https://doi.org/10.1186/s40851-023-00220-x

We report two Arctic species of incirrate octopods new to science. One is formally described here as Muusoctopus aegir Golikov, Gudmundsson & Sabirov sp. nov. while the other, Muusoctopus sp. 1, is not formally described due to a limited number of samples (all are immature individuals). These two species differ from each other, and from other Muusoctopus, especially in: 1) absence of stylets (in M. aegir sp. nov.); 2) proportions of mantle and head; 3) funnel organ morphology (W-shaped with medial and marginal limbs of equal length in M. aegir sp. nov., or medial are slightly longer; V V-shaped with medial limbs slightly longer and broader than marginal in Muusoctopus sp. 1); 4) sucker and gill lamellae counts; 5) relative arm length and sucker diameter; and 6) male reproductive system relative size and morphology. Species of Muusoctopus now comprise four of 12 known Arctic cephalopods. Additionally, this study provides: a) new data on the morphology and reproductive biology of M. johnsonianus and M. sibiricus, and a diagnosis of M. sibiricus; b) the equations to estimate mantle length and body mass from beak measurements of M. aegir sp. nov. and M. johnsonianus; c) a cytochrome c oxidase subunit I gene barcode for M. sibiricus; d) new data on the ecology and distribution of all studied species; and e) a data table for the identification of northern North Atlantic and Arctic species of Muusoctopus. publishedVersion