Haploniscus angolensis, Brökeland, Wiebke, 2010

Brökeland, Wiebke, 2010, Description of four new species from the Haploniscus unicornis Menzies, 1956 complex (Isopoda: Asellota: Haploniscidae), Zootaxa 2536, pp. 1-35 : 21

Haploniscus angolensis n. sp.

( Figs 12–14 )

Holotype: DIVA 1-HA213, adult male (stage VI), length 1.64 mm, coll.: RV Meteor, M48/1, DIVA 1 expedition, EBS station 344, 17°06.2’ S 4°41.7’ E, 5415 m, Angola Basin, southeast Atlantic, ZMH K- 42436.

Paratypes: DIVA 1-HA75, adult male, length 1.72 mm, same locality as holotype, ZMH K- 42437. DIVA 1-HA179, adult male, length 1.72 mm, coll.: RV Meteor, M48/1, DIVA 1 expedition, EBS station 348, 16°18.1’ S 5°27.2’ E, 5390 m, Angola Basin, ZMH K- 42438.

Etymology. Named after the type locality in the Angola Basin.

Diagnosis. Rostrum 0.5 head length. Pereonites 4 and 5 broadest, body tapering slightly anteriorly and posteriorly. Lateral margins of pleotelson tapering posteriorly; pleotelson process length 0.5 pleotelson length, 1.9 width. Pleopod 1 lateral margins tapering continuously into neck; distance basal margin–neck 0.7 total length, neck width 0.45 maximum width. Pleopod 2 endopod length 1.1 protopod length, 5.2 width; article 2 length 2.85 article 1 length.

Description (stage VI male). Body ( Fig. 12 A–D) length 2.5 width. Head length 0.6 width. Posterior angles of pereonites 2–7 and anterior angles of pereonites 2–5 acute. Pleotelson length 0.3 body length, 0.8 width.

Antenna 1 ( Fig. 13 B) peduncular article 1 length 1.5 width, with 3 penicillate setae and 1 simple seta distally; article 2 length 1.2 article 1 length, 2.0 width, with 3 penicillate setae distally; article 3 length 0.4 article 1 length, width 0.4 article 1 width, with 1 simple seta distally. Flagellum with 4 articles; article 1 shortest, with 1 penicillate seta; articles 2–4 of subequal length, about 2.9 article 1 length, articles 2 and 3 with 1 aesthetasc and 1 simple seta each; article 4 with 4 aesthetascs, 2 simple setae and 1 small penicillate seta.

Antenna 2 ( Fig. 13 A) peduncular article 2 with 1 simple seta; article 3 length 1.65 width, dorsal tooth, with 2 simple setae (one broken off); article 4 0.6 article 3 length, 0.9 width; article 5 length 1.3 article 3 length, 2.2 width; article 6 length 1.5 article 3 length, 4.2 width, with at least 3 penicillate setae. Flagellum with 10 articles, each article with up to 6 simple setae.

Pereopods ( Figs 13 C–G; 14A, B): Basis of all pereopods with 2 long simple setae ventrally; basis of pereopods 2–4 with 1–2 penicillate setae, of pereopods 5 and 6 with 2 or 3 penicillate setae, of pereopod 7 with 1 penicillate seta dorsally. Ischium with 1–2 simple setae dorsally and ventrally each. Merus with 2 setae of different length distoventrally and distodorsally. Carpus with 2 or 3 simple setae ventrally; distal carpus of pereopods 1–4 with 1 short simple seta (broken off on pereopods 5–7) dorsally, pereopods 2–7 with 1 penicillate seta (broken off on pereopod 3) distodorsally. Propodus with 3–5 setae ventrally, peropods 2–4 with 1 simple seta distodorsally (broken off on remaining pereopods), pereopods 2–7 with 1 penicillate seta distodorsally (broken off on some pereopods). Dactylus of pereopods 1 and 2 with 5, of pereopods 3–4 with 4 and of pereopods 5–7 with 1–2 setae near insertion of unguis.

Pleopod 1 ( Fig. 14 D) length 0.7 pleotelson length, about 2.1 width; widest part after 0.15 of its length.

Pleopod 2 ( Fig. 14 E) protopod length 1.8 width, with about 8 long setae along outer margin.

Pleopod 3 ( Fig. 14 C) endopod length 2.2 width. Exopod length 0.7 endopod length, 1.9 width.

Pleopod 4 ( Fig. 14 F) endopod length 1.8 width. Exopod length 0.6 endopod length, 2.7 width, plumose seta length about 1.8 exopod length.

Pleopod 5 ( Fig. 14 G) length 1.9 width.

Uropod ( Fig. 12 D) extending beyond posterior margin, not reaching tips of pleotelson processes.

Diagnosis. Found in the Angola Basin, Southeast Atlantic.

Figures

FIGURE 12. Haploniscus angolensis n. sp., male holotype, ZMH K- 42436; A, habitus, dorsal view; B, habitus, dorsal view; C, head, ventral view; D, posterior body, ventral view. Scale bar 1 mm.

FIGURE 13. Haploniscus angolensis n. sp., male paratype, ZMH K- 42437 (A, B) and ZMH K- 42438 (C – G); A, antenna 2, with lateral view of article 3; B, antenna 1; C, pereopod 1; D, pereopod 2; E, pereopod 3; F, pereopod 4; G, pereopod 5. Scale bars 0.1 mm.

FIGURE 14. Haploniscus angolensis n. sp., male paratype, ZMH K- 42438; A, pereopod 7; B, pereopod 6; C, pleopod 3; D, pleopod 1; E, pleopod 2; F, pleopod 4; G, pleopod 5. Scale bars 0.1 mm.