Tharyx circacutus Blake, 2015, new species

• Main Author: Blake, James A.
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2015
• Subjects: Biodiversity; Taxonomy; Animalia; Annelida; Polychaeta; Terebellida; Cirratulidae; Tharyx; Tharyx circacutus; Arctic
• Online Access: https://doi.org/10.5281/zenodo.5664952; http://treatment.plazi.org/id/9A3E87FEEB42FFFAD2F7FC3AFC36F8FB

Tharyx circacutus new species Figures 21‒22 Tharyx sp. N 1: Provisional name, Washington State Department of Ecology’s Marine Sediment Monitoring Program (MSMP); database (PSEMPMarineBenthicSpeciesList_sortable.xlsx) online: http://www.eopugetsound.org/species/custom-lists/306. Material examined .— Washington, Strait of Juan de Fuca, east central Port Angeles Harbor, coll. WA Department of Ecology, Puget Sound Ecosystem Monitoring Program (PSEMP), Sta. 1121, 18 June 2013, 48° 07.9026ʹ N, 123° 23.2853ʹ W, 29.5 m depth, in sandy silt, holotype (LACM-AHF Poly 6556), 12 paratypes (LACM-AHF Poly 6557). Description. Holotype 14.8 mm long, 0.43 mm wide for ca. 70 setigerous segments; largest paratype 16.4, mm long, 0.32 mm wide with 95 setigers. Body light tan in alcohol; with a cluster of lateral black pigment spots on posterior peristomium, otherwise without pigment except for a few cells surrounding nuchal organs on some specimens. Body long, slender, with first 15‒20 segments expanded, widest part of body with narrow, crowded segments each four times wider than long; following segments becoming as long as wide, with some in middle of body almost moniliform; far posterior segments narrowing to small pygidial segment. Body mostly cylindrical in cross section, with weakly developed ventral groove in far posterior segments. Prostomium triangular, tapering to pointed anterior margin; eyes absent (Figs. 21 A–B, 22A‒B); nuchal organs narrow slits surrounded by pigmented cells (Fig. 21 B). Peristomium wider than long, with one annulation visible laterally and dorsally (Figs. 21 A‒B, 22A); dorsal midline with a low, weakly developed ridge extending to end of peristomium (Figs. 21 A, 22A). Paired dorsal tentacles arising from posterior margin of peristomium; first pair of branchiae arising lateral and posterior to tentacles on posterior edge of peristomium (Figs. 21 A, 22A); second pair of branchiae arising from posterior margin of setiger 1, dorsal to notosetae. Parapodia low ridges from which setal fascicles arise; noto- ...