Axinella arctica

• Main Authors: Dinn, Curtis, Leys, Sally P., Roussel, Mylène, Méthé, Denise
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2020
• Subjects: Biodiversity; Taxonomy; Animalia; Porifera; Demospongiae; Halichondrida; Axinellidae; Axinella; Axinella arctica; Greenland; Lamarck; Buff; Labrador Sea
• Online Access: https://doi.org/10.5281/zenodo.3812521; http://treatment.plazi.org/id/03C687D0FFE4FF988FF7E3A5C1A3C7C1

Axinella arctica (Vosmaer, 1885) (Figure 2, Table 1) Original description: Phakellia arctica Vosmaer, 1885. 25, Pl. V, fig. 25-26 Synonyms: Axinella calyciformis (Lamarck, 1814), Spongia calyciformis Lamarck, 1814, Spongia pocillum Lamouroux, 1816, Tragosia arctica (Vosmaer, 1885), Tragosia calyciformis (Lamarck, 1814). Material examined North Labrador Sea: CMNI 2018 -0094, 60.468 N, 61.287 W, 412 m depth; CMNI 2018 -0099, 60.466 N, 61.278 W, 452 m depth. Western Greenland Shelf: CMNI 2018 -0146 67.967 N, 59.484 W, 877 m depth. Larne, Antrim, Northern Ireland: Axinella infundibuliformis BELUM.Mc38, 54.93 N, 5.742 W, 23 m depth. Near Lundy, Bristol Channel, England: Axinella infundibuliformis BELUM. Mc 41, 51.178 N, 4.683 W, 23 m depth. External appearance (Figure 2 A-D) Axinella arctica (Vosmaer, 1885) is a cup-like or flabellate shaped sponge. The species often forms an inverted, hollow cone that ranges 5–25 cm in diameter, and has a solid stalk. The sponge is pale yellow or buff to white in colour. The surface of the inner portions has many pin-hole sized openings; smaller openings are present on the outside surface. Dense longitudinal ribs extend from the stalk to the distal portions on the outside surface. The consistency is firm, and pieces will break off when bent more than 45°. The walls of the specimens are up to 0.5 cm thick. The distal lip is hispid from protruding spicules. Spicules and skeleton (Figure 2 E–F) Megascleres are styles 401– 467 –561 x 13– 17 –25 μm, and oxeas 329– 386 –443 x 13– 18 –24 μm. No microscleres are present. The skeleton consists of dense axial tracts of oxeas with loose extra-axial fibres consisting of styles which form long spicule brushes at the surface. Oxeas connect the extra-axial fibres. Genetic data COI for CMNI 2018–0099 (GenBank MK570860) was sequenced. The species is a perfect match to GenBank sequence for Axinella infundibuliformis BELUM:Mc4438 (GenBank HQ379410.1) based on 539 of 584 nucleotides. Although no apparent genetic difference in the COI mtDNA region ...