Haploniscus machairis Brökeland, 2010, n. sp.
Creators: name: Brökeland, Wiebke
Publisher: name: Zenodo
Year: 2010
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Isopoda
Haploniscidae
Haploniscus
Haploniscus machairis

description: Haploniscus machairis n. sp.
(Figs 9–11)
Holotype: DIVA 2-HA510, adult male (stage VI), length 1.51 mm, coll.: RV Meteor, M63/2, DIVA 2 expedition, EBS station 90-7, 0°40.49’ N 5°29.71’ W, 5142 m, Guinea Basin, southeast Atlantic, ZMH K- 42431.
Paratypes: DIVA 2-HA416, adult male, length 1.55 mm, same locality as holotype, ZMH K- 42432. DIVA 2-HA235–237, -HA331, adult males, length 1.45–1.54 mm, coll.: RV Meteor, M63/2, DIVA 2 expedition, EBS station 89-6, 0°42.95’ N 5°31.29’ W, 5142 m, Guinea Basin, ZMH K- 42433. DIVA 1-HA56, adult male, length 1.49 mm, coll.: RV Meteor, M63/2, DIVA 1 expedition, EBS station 318-1, 22°20.0’ S 3°18.3’ E, 5125 m, Angola Basin, ZMH K- 42434. DIVA 1-HA264, adult male, length 1.63 mm, coll.: RV Meteor, M63/2, DIVA 1 expedition, EBS station 340-1, 18°18.3’ S 4°41.3’ E, 5395 m, Angola Basin, ZMH K- 42435.
Etymology. The Greek machairis is the diminutive for machaira, the name for a bent sword. The name refers to the rostrum, which has a similar shape.
Diagnosis. Rostrum 0.5 head length. Pereonites 4 and 5 broadest, body tapering anteriorly and posteriorly; posterior angles of pereonite 4 and anterior angles of pereonite 5 slightly produced. Lateral margins of pleotelson tapering posteriorly. Pleotelson process length 0.5 pleotelson length, 2.0 width. Pleopod 1 lateral margins tapering continuously towards neck, slightly convex; distance basal margin–neck 0.8 total length, neck width 0.5 maximum width. Distolateral margins with minute process each. Pleopod 2 inner margin concave; endopod length 2.8 protopod length, 10.0 width; article 2 length 4.3 article 1 length.
Description (stage VI male). Body (Fig. 9 A–C) length 2.6 width. Head length 0.6 width. Posterior angles of pereonites 2–7 and anterior angles of pereonites 3–5 acute. Pleotelson length 0.3 body length, 0.9 width.
Antenna 1 (Fig. 10 G) peduncular article 1 length 1.8 width, with 3 penicillate setae distally; article 2 length 1.05 article 1 length, 2.2 width, with 2 simple and 4 penicillate setae distally; article 3 length 0.3 article 1 length, width 0.5 article 1 width, with 2 simple setae distally. Flagellum with 4 articles; article 1 shortest, articles 2–4 of subequal length about 1.5 article 1 length; article 2 with 1 aesthetasc and 1 simple seta; article 3 with 2 aesthetascs, article 4 with 2 aesthetascs and 2 simple setae.
Antenna 2 (Fig. 10 F) peduncular article 2 with 1 simple seta; article 3 length 1.75 width, with 1 simple seta distally and 2 simple setae dorsally, dorsal tooth with 2 simple setae; article 4 0.8 article 3 length, 1.4 width, with 2 simple setae; article 5 length 1.6 article 3 length, 2.5 width, with at least 7 simple setae; article 6 length 2.2 article 3 length, 5.0 width, with at least 3 penicillate and 4 simple setae. Flagellum with 11 articles, each article with up to 4 simple setae.
Pereopods (Figs 10 A–E; 11A, B): Basis of all pereopods with 2 long simple setae ventrally; basis of pereopods 2–4 with 2 penicillate setae, of pereopods 5–6 with 3 penicillate setae, of pereopod 7 with 1 penicillate seta dorsally. Ischium with 1 seta dorsally and 1 or 2 setae ventrally. Merus with 2 simple setae of different length distodorsally, and 2 or 3 setae distoventrally. Carpus with 2 or 3 simple setae ventrally; with 1 short simple seta, pereopods 2–7 with 1 penicillate seta distodorsally. Propodus with 2–5 setae ventrally, peropods 1–3 with 1 simple seta distodorsally (broken off on pereopods 4–7), pereopods 2–7 with 1 penicillate seta distodorsally (broken off on pereopod 6). Dactylus of pereopods 1–4 with 4 and of pereopods 5–7 with 2 setae near insertion of unguis.
Pleopod 1 (Fig. 11 C) length 0.6 pleotelson length, 1.9 width; widest part after 0.2 of its length.
Pleopod 2 (Fig. 11 D) protopod length 2.1 width, with about 9 long setae along outer margin.
Pleopod 3 (Fig. 11 E) endopod length 1.9 width. Exopod length 0.7 endopod length, 1.7 width.
Pleopod 4 (Fig. 11 F) endopod length 2.3 width. Exopod length 0.6 endopod length, 2.7 width, plumose seta broken off.
Pleopod 5 (Fig. 11 G) length 2.2 width.
Uropod (Fig. 9 C) extending beyond posterior margin, not reaching tips of pleotelson processes.
Distribution. Found in the Guinea Basin and Angola Basin, Southeast Atlantic.
description: Published as part of Brökeland, Wiebke, 2010, Description of four new species from the Haploniscus unicornis Menzies, 1956 complex (Isopoda: Asellota: Haploniscidae), pp. 1-35 in Zootaxa 2536 on page 17, DOI: 10.5281/zenodo.196630