Mideopsis persicus, Pešić & Saboori, 2015

Pešić, Vladimir & Saboori, Alireza, 2015, A new species of the water mite genus Mideopsis Neuman, 1880 from South Iran (Acari, Hydrachnidia), Ecologica Montenegrina 2 (2), pp. 112-116 : 114-115

Mideopsis persicus n. sp.

( Figs. 1-2)

Material examined. Holotype male ( MNHP), dissected and slide mounted, Iran, Fars Province, Firooz Abad city, Kay Zarrin village , stream, 1711 m asl., 28°53'N, 52°32'E, Pešić & Saboori.

Diagnosis. Dorsal shield in the centre slightly elevated. Ejaculatory complex with well sclerotized anterior keel, anterior ramus narrower, wedge-shaped. P-2 slender (length/height ratio 1.4); P-4 ventral projection straight, with two tips directed ventrally.

Description. Colour dark yellowish. Idiosoma rounded, ventral shield length/width 703/709. Dorsal shield in the centre slightly elevated, with anteriorly diverging lines of particularly fine porosity little distinct, dorsal shield length/width 659/563 (ratio 1.17). Genital field length/width 194/116, gonopore length/width 137/61, ratio 2.25, postgenital area shorter (88 µm, 13% dorsal shield length), excretory pore closer to posterior idiosoma margin (distance 16 µm). Ejaculatory complex length 234, with strongly sclerotized anterior keel, anterior ramus wedge-shaped ( Fig. 1D).

Palp: total length 228, dorsal length/height, dorsal length/height ratio: P-1, 28/34, 0.82; P-2, 60/42- 46, 1.32-1.38; P-3, 34/34, 1.0; P-4, 67/24 (basal), 2.85, 35 (incl. projection), 1.9; P-5, 39/16, 2.3; P-2 slender (length/height ratio 1.4), ventral margin slightly convex; P-3 ventral margin concave, distal margin convex; P-4 ventral projection directed ventrally, with two tips both flanked by a fine subterminal seta; distal part of segment slightly narrower than basal part, with 3 subapical setae, two fine, dorsally and laterally, one slightly thicker and stiff, ventrally ( Fig. 1C). Gnathosoma length 128, chelicera length 168.

Legs: dorsal lengths of I-L: 52, 60, 57, 72, 96, 125; II-L: 56, 68, 66, 77, 103, 122; III-L: 60, 72, 64, 92, 118, 113; IV-L: 75, 88, 80, 106, 131, 131.

Etymology. Named after the country where the type locality is located.

Remarks. Due to the almost circular idiosoma, P-2 more slender and ventral extension of P-4 straight or only slightly curved, with two tips directed ventrally, the new species resembles Mideopsis orbicularis and M. roztoczensis . The latter is a rhitrophilous species, often confused with M. orbicularis , and can be distinguished from the new species by the following features, 1) dorsal shield high, convexly elevated, 2) postgenital area larger and excretory pore more away from posterior margin of idiosoma, and 3) different shape of the male ejaculatory complex (anterior ramus wide, with a characteristic wide arrow-shaped delimited area, Fig. 3B). In addition to the shape of male ejaculatory complex (weakly sclerotized anterior keel, anterior ramus rounded, with a characteristic horse-shoe shaped delimited area, Fig. 3A), Mideopsis orbicularis is clearly different from the new species by its habitat preference for standing waters.

Habitat. Middle order stream; it was found together with Torrenticola nana Di Sabatino & Gerecke, 2003 , Hygrobates fluviatilis (Ström, 1768) , H. angustipalpis Viets, 1982 and Monatractides sp.

Distribution. South Iran, know only from the locus typicus.