Onisimus barentsi Stebbing 1894

• Main Authors: Berge, Jørgen, Vader, Wim, Johnsen, Jan Roger
• Format: Other/Unknown Material
• Language: unknown
• Published: 2007
• Subjects: Biodiversity; Taxonomy; Animalia; Arthropoda; Malacostraca; Amphipoda; Uristidae; Onisimus; Onisimus barentsi; Canada; Greenland; Lowry; Dunbar
• Online Access: https://zenodo.org/record/6248998; https://doi.org/10.5281/zenodo.6248998

Onisimus barentsi (Stebbing, 1894) Figure 1–4 Paronesimus barentsi Stebbing 1894: 14; Stephensen 1932: 354, 1935: 51; Gurjanova 1936: 34, 1951: 198, 1962: 143; Dunbar 1954: 715; Shoemaker 1955: 6; Barnard 1958: 98; Brunel 1970: 35; Watling 1979: 266; Palerud & Vader 1991: 42. Onisimus barentsi Lowry & Stoddart 1993: 176 Onisimus krassini Gurjanova 1951: 175. New synonomy. Type locality West of Novaja Zemlya: 75 ° 49 'N 53 ° 42 'E, 125m. Diagnosis Antenna 1 peduncle article 1 produced anterodistally (nose). Uropod 1 peduncle length about 1.5 times rami. Cephalic lobe rounded. Coxa 1 expanded ventrally. Pereopod 1 propodus length 1.5 times carpus length, palm clearly shorter than dactylus. Telson cleft 40 %. Material examined CRU, female, 12mm, Godthaab-Exp St 139, 71 ° 21 ’ N 54 ° 29 ’ W. Greenland, 1 spm. (Det: O. plautus.); CMNC 1998 -0010, female 5mm, Northumberland Canada, 35m; Type material of O. krassini at the ZMS. Description (based upon female 12mm, adult) Head and body: Head as long as pereon 1. Cephalic lobe little extended forward, rounded, dorsal margin straight and ventral margin convex. Eyes oval. Urosomite 1 with slight dorsal depression. Antennae: Antenna 1 as long as cephalon and next 1.5 body segment; peduncle article 1 slightly longer than head, longer than deep, produced anterodorsally; accessory flagellum length 0.6 times primary flagellum, 5 -articulate, article 1 clearly shorter than the rest of flagellum, as long as primary flagellum article 1; primary flagellum 0.9 times peduncle, 10 -articulate, article 1 as long as next 3 articles combined; callynophore present; calceoli absent on flagellum. Antenna 2 about 1.2 times as long as antenna 1; flagellum 12 -articulate; peduncle article 4 clearly longer than article 5, article 5 as long as the three first articles in flagellum; calceoli absent on flagellum. Mouthparts: Epistome and labrum weakly convex, labrum not in front of epistome. Mandible incisor with convex margin; left lacinia mobilis present; 3 accessory setae present on ...