Atractides linearis Lundblad 1927
Creators: name: Pešić, Vladimir
name: Smit, Harry
name: Gerecke, Reinhard
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Trombidiformes
Hygrobatidae
Atractides
Atractides linearis

description: Atractides linearis (Lundblad, 1927)
(Figs. 7–10)
Megapus linearis Lundblad 1927a: 333.
Material examined. South Africa, Western Cape province: SA 9 25/24 /2 (1/1/1 mounted). KwaZulu-Natal province: SA 12 1/2 /0 (1/1/0 mounted); SA 17 0/1/0; SA 18 1/0/0; SA 22 0/1/0; SA 24 2/2 /0; DC 92 84 0/1/0. Limpopo province: SA 25 3/1 /0. Mpumalanga province: DC 78 84 0/1/0; DC 84 84 10/6 /0; DC 85 84 1/0/0; DC 86 84 1/0/0; DC 87 84 2/21 /0 (1/0/0 mounted). Eastern Cape province: DC 103 84 4/28 /4 (0/0/1 mounted).
General features. Dorsal integument lineated; muscle attachments unsclerotized. Coxal field: apodemes Cx-II in an acute angle. Genital field: Ac in a weakly curved line. Excretory pore: unsclerotized; Vgl-1 close to Vgl-2 and often fused (in older specimens). Palp: sexual dimorphism, in both sexes P-2 distoventrally protruding; P-4 sword seta between ventral hairs, nearer to distoventral hair. I-L-5 distally protruding near insertion S-1, S-1 and S-2 bluntly pointed, interspaced, S-2 basally enlarged; I-L-6 curved, inflated proximally, from the centre to the claw furrow with parallel dorsal and ventral margins; leg claw without dorsal clawlets.
Morphology. Male (SA 9, in parentheses SA 12, in square parentheses DC 87 84). Idiosoma L/W (423)/(328); glandularia maximum diameter 23 (19) [22]; coxal field L 288 [295]; Cx-III W 328 [347]; Cx-I+II mL 100, lL 188. Genital field (Fig. 7A, 8A): anterior margin slightly concave; L/W 91 (97) [92]/102 (115) [99]; L Ac 1-3: 24 (29– 32) [30], 28 (30–31) [29–32], 32 (38–39) [29]; ejaculatory complex L (103) [99].
Palp (Figs. 7C, 8C): total L 254 (229) [265], dL: P-1, 28 (28) [27]; P-2, 62 (52) [59]; P-3, 54 (49) [60]; P-4, 81 (71) [87]; P-5, 29 (29) [32]; L ratio P-2/P-4, 0.77 (0.73) [0.68]; P-2 ventral margin distally protruding, P-3 stout; capitulum vL [132].
I-L (Figs. 7B, 8B): I-L-5 dL 159 (137) [165], vL 100 (91) [105], dL/vL ratio 1.59 (1.51) [1.57], HB 45 (41) [46], dL/HB 3.53 (3.34) [3.59], S-1 L 75 (67) [82], L/ W 9.7 (7.9) [9.7], S-2 L 63 (54) [69], L/ W 5.1 (4.4) [5.2], distance S-1-2, 17 (12) [21], L ratio S-1/2, 1.2 (1.24) [1.2]; I-L-6 L 115 (100) [124], HB 18 (18) [19], L/HB ratio 6.5 (5.6) [6.7]; L ratio I-L-5/6, 1.38 (1.37) [1.33].
Female (SA 9, in parentheses SA 12). Idiosoma L/W L/W (531)/(397); glandularia maximum diameter 25 (22); coxal field L 363 (303); Cx-III W 420 (356); Cx-I+II mL 105 (91), lL 219 (195). Genital field (Fig. 9B): L/W 158/ 161; genital plate L 109 (108–109); pregen W 89, L Ac 1–3: 35 (35–41), 40 (35–40), 32 (34–35).
Palp (Fig. 7D): total L 332 (273), dL: P-1, 35 (30); P-2, 74 (63); P-3, 85 (66); P-4, 101 (84); P-5, 37 (30); L ratio P-2/P-4, 0.73 (0.75); palp much slender than in male, P-2 with a ventrodistal hump; capitulum vL 141; chelicera total L 215.
I-L (Fig. 9A): I-L-5 dL 215 (175), vL 137 (115), dL/vL ratio 1.57 (1.52), HB 57 (48), dL/HB 3.77 (3.64), S-1 L 103 (77), L/ W 10.1 (10.0), S-2 L 80 (72), L/ W 5.0 (5.2), distance S-1-2, 29 (22), L ratio S-1/2, 1.29 (1.07); I-L-6 L 154 (113), HB 18.5 (16), L/HB ratio 8.3 (7.0); L ratio I-L-5/6, 1.4 (1.54).
Deutonymph (collected at SA 9 and suspected to represent this species). Idiosoma L/W 303/229; integument dorsally lineated; muscle attachments unsclerotized; coxal field L 169; Cx-III W 199; Cx-I+II mL 47, lL 104; provisional genital field with two pairs of Ac (Fig. 10A), L/W 47/55; excretory pore smooth; Vgl-1 not fused to Vgl-2
Palp: total L 150, dL: P-1, 16; P-2, 33; P-3, 31; P-4, 48; P-5, 22; L ratio P-2/P-4, 0.69.
I-L (Fig. 10B): I-L-5 dL 89, vL 70, dL/vL ratio 1.27, HB 31, dL/HB 2.9, S-1 L 45, L/ W 8.8, S-2 L 43, L/ W 6.2, distance S-1-2, 0, L ratio S-1/2, 1.05; I-L-6 L 63, HB 15, L/HB ratio 4.1; L ratio I-L-5/6, 1.39.
Remarks. Due to the lineated integument, unsclerotized dorsal muscle attachments, unsclerotized excretory pore, P-2 distoventrally protruding in both sexes, and I-L-5 with S-1 and S-2 bluntly pointed and with a narrow setal interspace, the specimens examined from South Africa show general conformity with A. linearis (Lundblad, 1927). Considerable variation is found in the fusion of Vgl-1 and -2 (Vgl-1 free or fused to the medial margin of Vgl-2, in some cases asymetrically fused only on one side, but free on the other, see Fig. 8A) and in the anterior margin of the male genital field, being straight to slightly concave (Fig. 7A) or more indented (Fig. 8A).
Distribution. Kenya: Lundblad (1927a, b, 1952); South Africa: Eastern Cape province: K.O. Viets (1964a), present study; Western Cape province: present study; Mpumalanga province: K.O. Viets (1964a), present study; Limpopo province: present study.
description: Published as part of Pešić, Vladimir, Smit, Harry & Gerecke, Reinhard, 2011, New records of water mites of the genus Atractides Koch, 1837 (Acari: Hydrachnidia, Hygrobatidae) from South Africa, with descriptions of five new species, pp. 1-54 in Zootaxa 2986 on pages 8-13, DOI: 10.5281/zenodo.200656