Monatractides vafaei Pesic

Pesic, Vladimir & Saboori, Alireza, 2004, Water mite species of the genus Monatractides K. Viets (Acari: Hydrachnidia, Torrenticolidae) from Iran, with the description of two new species, Zootaxa 673, pp. 1-10 : 4-7

Monatractides vafaei Pesic sp. nov.

( Fig. 10–16 )

Type material: Holotype: male, dissected and slide mounted in Hoyer's fluid. Iran: IR46 Tehran Province, Charan stream in Charan village (35°54'34 N 51°7' 28E), 2107 m asl., 14.08.2003, leg. Pesic & Saboori; Paratypes: 8 males, same data as holotype, one of them dissected and slide mounted in Hoyer's fluid.

Other material: IR60 Markazi Province, Ghareh Chai stream, 30km after Tafresh city, ca. 2100 m asl., 24.08.2003, leg. Pesic, one male and one juvenile female, dissected and slide mounted in Hoyer's fluid.

Diagnosis (Males): Dorsal shield with a relatively wide frontal plate (L/ W 1.46 –1.57), shoulder plate with a posteriorly­directed ridge; medial suture line of Cx­2+3 relatively long; three pairs of knob­shaped protrusions at the margin of the gnathosomal bay; chelicerae with robust basal segment (ratio length/height 6.5–6.8); distal margins of P­2 and P­ 3 bearing denticles.

Description: Males (type material, in brackets male from IR60): Idiosoma ( Fig. 11 ) L 850–858 (852), W 658–671 (700); dorsal shield ( Fig. 10 ) L 692 (725), W 542 (542), L/W ratio 1.28 (1.34); dorsal plate L 608–617 (650); shoulder plate L/W 217–221 (233)/92–96 (92), L/W ratio 2.3–2.36 (2.5), with a posteriorly­directed ridge; frontal plate L/W 150– 165 (146)/100–105 (100), L/W ratio 1.5–1.57 (1.46); shoulder/frontal plate L ratio 1.34– 1.45 (1.6); gnathosomal bay L 170–175 (171), its lateral margin with knob–shaped protrusions: one pair at the apical tip of Cx­1, two further pairs distally and proximally from the subapical seta; Cx­1 L 304–305 (296), median L 127–138 (123); Cx­2+3 median L 119– 129 (125); ratio Cx­1 L/Cx­2+3 median L 2.2–2.4 (2.4); Cx­1 median L/Cx­2+3 median L 0.98–1.16 (0.98); genital field L/W 156–158 (163)/133 (138), L/W ratio 1.17–1.19 (1.18), ejaculatory complex L 213–219 (238); distance genital field–excretory pore 183–192 (181); genital field–caudal body margin 283–292 (288); gnathosoma ( Fig. 15 ) ventral L 188–208 (190), dL 223–231 (225); chelicera ( Fig. 16 ) L 229–242 (242), H 35.4 (39.6), L/ H ratio 6.5–6.8 (6.1), cheliceral basal segment L 190–198 (200), claw L 44–46 (44), basal segment/claw L ratio 4.3 (4.5); palp ( Figs. 13–14 ) total L 242–250 (246), dorsal length of palp segments: P­1 27 (29), P­2 71–75 (73), P­3 50 (48), P­4 63–65 (63), P­ 5 31–33 (33); relative length (given as % of total length) of palp segments: P­1 10.8–11.2 (11.8), P­2 29.3–30.0 (29.7), P­3 20.0–20.7 (19.5), P­4 26.0 (25.6), P­5 13.2–13.6 (13.4); P­2/P­4 ratio 1.1–1.15 (1.2); distal margins of P­2 and P­3 with denticles, P­4 with a denticle near insertion of the ventral hairs and a strong mediodistal peg­like seta.

In the following, we give additional measurements of the specimens from IR60 which are suspected to represent the juvenile female of Monatractides vafaei sp. nov. Idiosoma L 850, W 742; dorsal shield ( Fig. 12 ) L 704, W 550, L/W ratio 1.28; dorsal plate L 608; shoulder plate L/W 233/104, L/W ratio 2.24; frontal plate L/W 156/113, L/W ratio 1.38; shoulder/frontal plate L ratio 1.49; gnathosomal bay L 200; Cx­1 L 300, median L 133; Cx­2+3 median L 96; ratio Cx­1 L/Cx­2+3 median L 2.25; Cx­1 median L/Cx­2+3 median L 1.38; genital field L/W 217/204,L/W ratio 1.06; distance genital field–excretory pore 196; gnathosoma ventral L 229, dorsal length 263; chelicera L 263, H 42, L/H ratio 6.3, cheliceral basal segment L 213, claw L 50, basal segment/claw L ratio 4.3; palp total L 275, dorsal length and relative length (given in parentheses as % of total length) of palp segments: P­1 31 (11.3), P­2 81 (29.5), P­3 56 (20.4), P­4 72 (26.2), P­5 35 (12.7); P­2/P­4 ratio 1.13.

Discussion: In the combination of the presence of three pairs of knob­shaped protrusions at the margin of the gnathosomal bay, a rather long medial suture line of Cx­2+ 3 in males, and distal margins of P­2 and P­3 bearing al least one pointed denticle, Monatractides vafaei sp. nov. is similar to M. algeriensis . As compared with M. algeriensis (data in parentheses from Di Sabatino et al. 1992), M. vafaei is characterized by the following features: ejaculatory complex shorter, L 213–238 (L 256–280), minor genital field dimensions, L/W 156–163/133–138 (L/W 175–187/162–175), chelicera relatively thicker, L/H 6.5–6.8 (L/H 7.2–8.3), gnathosomal rostrum less elongated and the distal margins of P­2 and P­3 bearing more that one denticle.

The male from Markazi Province is in good agreement with the specimens from the locus typicus. Differences are found in a thicker chelicera (L/H 6.1) and a relatively longer shoulder plate (shoulder/frontal plate L 1.6). In view of the good agreement in other measurements these differences are most probably age­depending and/or due to geographical variability.

Etymology: The species is named after Reza Vafaei (Head of the Department of Entomology, Islamic Azad University in Arak, Iran).

Biology: Rhitrobiont.

Distribution: Iran, only known from the type localities in Markazi and Tehran Provincies.

Figures

FIGURES 10 – 16. Monatractides vafaei sp. nov., (10 – 11, 13 – 16 = male; 12 = female): 10 = dorsal shield; 11 = idiosoma, ventral view; 12 = dorsal shield; 13 = palp, lateral view; 14 = palp, medial view; 15 = gnathosoma; 16 = chelicera. Bars = 0.1 mm.