Atractides comorosensis Smit & Pesic

Smit, Harry, Pesic, Vladimir & Mary-Sasal, Nathalie, 2009, New species of water mites from the Comoros (Acari: Hydrachnidia), Zootaxa 2213, pp. 47-56 : 53-56

Atractides comorosensis Smit & Pesic n. sp.

( Figs. 18–25 )

Material examined. Holotype female, Mro oua Longoni (Longoni River), Mayotte, Comoros , 12°44'21,12" S 45°9'54,97" E, 16 May 2006, leg. N. Mary ( MNHN). Paratypes: one male and one female (damaged, palps lacking), same date as holotype, 14 May 2006, leg. N. Mary ( ZMAN); one female, affl. of Bouyouni River, Mayotte, Comoros , 12°45'24,52" S 45°8'51,11" E, 15 May 2006, leg. N. Mary.

Further records. 0/6/0, Mro oua Ourouveni, mouth (Ourouveni River, mouth), Mayotte, Comoros , 16 May 2006, leg. N. Mary.

Diagnosis. Integument dorsally striated; dorsal muscle attachment plates unsclerotized; I-Leg-5 longish, S-1 and -2 with narrow interspace, S-1 long, slightly bent inwards, distally thickened and with truncate tip, S- 2 shortened, with blunt tip; I-Leg-6 relatively long and slender; palp: without sexual dimorphism, P-2 ventral margin forming a pointed distal angle, P-4 rather slender, with a denticle near proximal hair, sword seta near distoventral hair; excretory pore smooth; Vgl-1: not fused to Vgl-2 (this character is unstable; fused in older specimens).

Description. Male (holotype, in parentheses measurements of paratype): Idiosoma L/W 464 (459)/345 (341). Integument dorsally striated. Dorsal muscle attachment plates unsclerotized. Coxal field ( Fig. 19 ): L 300, Cx-1+2 mL 92 (97), Cx-1+2 lL 203. Palp ( Figs. 21–22 ): palp total L 313 (316), dL: P-1 32 (30); P-2 70 (70); P-3 71 (74); P-4 108 (109); P-5 32 (33); %L: P-1 10.2 (9.5); P-2 22.4 (22.2); P-3 22.7 (23.4); P-4 34.5 (34.5); P-5 10.2 (10.4); L P-2/P-4 0.65 (0.64); P-2 ventral margin forming a pointed distal angle; P-4 rather slender, with a denticle near proximal hair, sword seta near distoventral hair. Genital field ( Fig. 18 ): with nearly straight or slightly convex anterior margin, Ac small, in an curved line, L/W 82 (86)/100 (100); L Ac- 1–3: 23 (22–17)-21 (19–21)-24 (24–27); excretory pore smooth; Vgl-1: fused to Vgl-2 (not fused in paratype).

I-Leg ( Fig. 20 ): I-Leg-5 thickened, S-1 and -2 with narrow interspace, S-1 long, slightly bent inwards, distally thickened and with truncate tip, S-2 shortened, with blunt tip; I-Leg-6 relatively long and slender; I- Leg-5 dL 182 (179), vL 130 (130), dL/vL 1.4 (1.4), HB 59 (62), dL/HB 3.1 (2.9), S-1 L 99 (102), L/W 9.3 (9.6), S-2 L 79 (82), L/W 7.4 (6.6), distance of sword setae at I-Leg-5 11 (13), L S-1/2 1.25 (1.24); I-Leg-6 L 135 (138), HB 18 (19), L/HB 7.5 (7.3); L I-Leg-5/6 1.35 (1.3).

Female (from affl. of Bouyouni River, in parentheses measurements of specimen from Ourouveni mouth): Idiosoma L/W 503 (703)/378 (531). Coxal field ( Fig. 25 ): coxal field L 322 (345), Cx-3 W 384, Cx-1+2 mL 89 (103), Cx-1+2 lL 209 (231). Palp ( Fig. 24 ): palp total L 356 (349), dL: P-1 35 (35); P-2 76 (71); P-3 88 (89); P-4 118 (115); P-5 39 (39); %L: P-1 9.8 (10.0); P-2 21.4 (20.3); P-3 24.7 (25.5); P-4 33.2 (33.0); P-5 11.0 (11.2); L P-2/P-4 0.64 (0.62); P-4 more slender than in male. Genital field ( Fig. 25 ): Ac in an obtuse triangle, L/W 117/139, genital plate L 79 (85); L Ac-1-3: 25 (26)-26 (26)-27 (27), egg maximum diameter in ovigerous female from Langoni river (n=2) 131-144; excretory pore smooth; Vgl-1: not fused to Vgl-2 (fused in specimen from Ourouveni mouth).

I-Leg ( Fig. 23 ): I-Leg-5 dL 211 (213), vL 161 (151), dL/vL 1.3 (1.41), HB 74 (71), dL/HB 2.85 (3.0), S-1 L 124 (115), L/W 9.14 (9.5), S-2 L 106 (93), L/W 6.5 (6.8), distance of sword setae at I-Leg- 5 17-20 (23), L S-1/2 1.17 (1.24); I-Leg-6 L 167 (165), HB 20 (19), L/HB 8.4 (8.7); L I-Leg-5/6 1.26 (1.29).

Etymology. The species is named for its occurrence on the Comores.

Remarks. The new species resembles Atractides damkoehleri (K. Viets, 1916) , due the presence of the striated integument, P-2 without ventrodistal projection in both sexes and S-1 distally truncated (see K.O.Viets 1964 for an analysis of diagnostic characters of this species). Atractides comorosensis n.sp. differs from A. damkoehleri (in parentheses) in P-2 with ventral margin distally ending in an acute or right angle (not forming an acute or right angle), a male genital field with small and more roundish Ac arranged in a curved line (Ac subtriangular in shape, arranged in more or less triangular position), and I-Leg-6 longer and much more slender (shorter and thicker, more sausage-shaped).

Figures

FIGURES 18 – 22. Atractides comorosensis n. sp., male (18, 20 – 22 holotype; 19 paratype): 18 = genital field; 19 = idiosoma, ventral view; 20 = I-Leg- 5 and – 6; 21 = palp, medial view (P- 1 missing); 22 = palp, lateral view. Scale bars = 100 µm.

FIGURES 23 – 25. Atractides comorosensis n. sp., paratype female: 23 = I-Leg- 5 and – 6; 24 = palp, medial view; 25 = idiosoma, ventral view. Scale bars = 100 µm.