Normanion ruffoi Diviacco& Vader, 1988

Kilgallen, Niamh M., Myers, Alan A. & Grath, David M, 2006, A revision of the North Atlantic amphipod genus Normanion (Crustacea: Amphipoda: Lysianassoidea), Zootaxa 1363, pp. 1-21 : 15-19

Normanion ruffoi Diviacco& Vader, 1988

Figures 10–12

Normanion ruffoi Diviacco and Vader, 1988: 122 , figs 3–5. — Diviacco and Ruffo, 1989: 514, figs 351–352.

? Normanion sarsi . — Ledoyer, 1977: 381, fig 19B.

Normanion quadrimanus . —? Costello et al., 1989: 34.

Type material. HOLOTYPE: Ovigerous female, 3.5 mm, MSNV No. 766–769.

Type locality. Marseille.

Material examined. Holotype, female, 3.5 mm, from Marseille, 180–360 m, bathyal mud, MSNV No. 766–769; 8 specimens, 2.5–5 mm, from Trondhjemsfjord, ZMO F13172; 2 specimens, 2.5–3 mm, from the west coast of Ireland, 52º49'N 11º40'W, 158.4 m, coarse sand and shells, collected by N.M Kilgallen, 3/10/2004.

Description. Lateral cephalic lobes subquadrate. Eyes present. Antenna 1 slightly shorter than antenna 2, flagellum 5-articulate, article 1 slightly longer than article 2; callynophore present; accessory flagellum 3-articulate. Antenna 2 flagellum 3-articulate; calceoli absent. Mandible palp attached proximal to molar, molar setose. Maxilliped palp 3-articulate, reaching to tip of inner plate.

Gnathopod 1 subchelate; coxa 1 slightly shorter than coxa 2, rounded distally; ischium elongate, more than twice as long as broad; carpus shorter than propodus; propodus subequal in length and breadth, palm transverse, striated, and posterodistally delimited by 2 robust setae and a central spine; inner margin of dactylus may be smooth or have small, blunt serrations. Gnathopod 2 minutely chelate; carpus almost twice as long as propodus. Pereopods 3–4 dactylus small. Coxa 5 produced into a posterior lobe; pereopod 5 basis twice as long as broad, produced beyond ischium; dactylus extremely long and slender.

Coxa 6 produced into a posterior lobe; pereopod 6 basis twice as long as broad, not produced beyond ischium. Pereopod 7 basis subrectangular, slightly longer than broad, not produced beyond ischium.

Epimeron 1 anterodistal corner quadrate; epimeron 3 posterodistal corner rounded. Urosomite 1 with dorsal depression. Uropod 1 rami subequal; uropod 2 rami distinctly unequal, inner ramus much longer than outer ramus; uropod 3 rami subequal. Telson entire.

Distribution. Widespread from the Mediterranean Sea, west coast of Ireland, and to the Norwegian Sea, 120– 360 m.

Remarks. N. ruffoi ’s unique combination of characters are the 3-articulate maxilliped palp, the smooth and striated gnathopod 1 palm, and the subequal uropod 3 rami.

As with N. quadrimanus above, the examined material of N. ruffoi showed variation in the form of the gnathopod 1 dactylus. While some specimens have a smooth, or slightly uneven inner margin, others have small blunt serrations. Like N. quadrimanus , other characters remain stable, and this is the only variation.

Figures

FIGURE 10. Normanion ruffoi (Diviacco & Vader, 1988), female, 3.5 mm (holotype): (A) gnathopod 2 propodus; (B) gnathopod 2; (C) pereopod 4; (D) gnathopod 1 dactylus (non-type— ZMO F 13172); (E) gnathopod 1; (F) pereopod 3. Scale bars: 1 = 0.1 mm (D); 2 = 0.2 mm (B – C, E – F); 3 = 0.1 mm (A)

FIGURE 11. Normanion ruffoi (Diviacco & Vader, 1988), female, 3.5 mm (holotype): (A) pereopod 5; (B) uropod 2; (C) pereopod 6; (D) uropod 1; (E) uropod 3; (F) telson (non-type—ZMO F 13172); (G) pereopod 7. Scale bars: 1 = 0.2 mm (A, C, G): 2 = 0.1 mm (F); 0.125 mm (B, D – E).

FIGURE 12. Normanion ruffoi Diviacco & Vader, 1988, female, 3.5 mm (holotype): (A) habitus (non-type—ZMO F 13172); (B) head and antennae; (C) epimera 1 – 3; (D) right maxilliped; (E) left mandible. Scale bars: 1 = 0.8 mm (A – B); 2 = 0.4 mm (C); 0.1 mm (D – E).