Monatractides (Monatractides) rivulus Pešić & Smit, 2012, sp. nov.
Creators: name: Pešić, Vladimir
name: Smit, Harry
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Trombidiformes
Torrenticolidae
Monatractides
Monatractides rivulus

description: Monatractides (Monatractides) rivulus sp. nov.
(Fig. 8A–G)
Type series. Holotype, male, dissected and slide mounted, Indonesia, New Guinea, West Papua province, small stream ca. 2.5 km S of Mokwam, 08.xi.2011, 1˚ 05.881 S, 133˚ 54.272 E, alt. 1612 m asl. Paratypes: 2/0/0, same data as holotype, one male dissected and slide mounted.
Diagnosis (Female unknown). Idiosoma elongated (dorsal shield L/W ratio 1.6); frontal plates broad (L/W ratio 1.5–1.9); shoulder plates swollen anteriorly; the area of primary sclerotization of the dorsal plate with four dorsoglandularia; capitular bay slender (L/W ratio 2.9–3.1); medial suture line of Cx-2+3 relatively long (100 μm); genital field relatively slender (L/W ratio 1.3–1.4); posterior suture line of Cx-4 well accentuated and directed posterolaterally; excretory pore posterior to the line of primary sclerotization, Vgl-2 posterior and well separated to excretory pore; distal margins of P-2 and -3 without denticles, P-4 ventral hairs small, inserted more distally; I-L-6 relatively stout (L/H ratio 2.6–2.7).
Description. Male (holotype, in parentheses paratype): Idiosoma: (ventral view: Fig. 8B) L 997 (988), W 650 (625); dorsal shield (Fig. 8A) L 838 (809), W 525 (514), L/W ratio 1.6 (1.57); dorsal plate 766 (750); shoulder plate L 247–250 (231–244), W 97–98 (91–97), L/W ratio 2.55 (2.5–2.6); frontal plate L 143–148 (153–158), W 94–96 (84–87), L/W ratio 1.52–1.54 (1.76–1.88); shoulder/frontal plate L ratio 1.67–1.75 (1.5–1.6); capitular bay L 186 (183), W 60 (62), L/W ratio 3.1 (2.9); Cx-1 total L 345 (341), Cx-1 medial L 159 (156), Cx-2+3 medial L 102 (102); ratio Cx-1 L/Cx-2+3 medial L 3.4 (3.3); Cx-1 medial L/Cx-2+3 medial L 1.6 (1.5); genital field L/W 206 (202)/150 (153), L/W ratio 1.37 (1.32), ejaculatory complex (Fig. 8F) L 270 (244); distance genital field–excretory pore 203 (203), genital field–caudal idiosoma margin 331 (328); capitulum (Fig. 8C) ventral L 220 (206); chelicera total L 232 (237); palp (Figs. 8D–E) total L 235 (229), dL: P-1, 34 (34); P-2, 66 (66); P-3, 48 (45); P-4, 65 (62); P-5, 22 (22); L P-2/P-4 ratio, 1.02 (1.06); L I-4–6 (Fig. 8G): 139 (135), 138 (137), 140 (140); I-L-6 L/ H ratio, 2.6 (2.7)
Female. Unknown.
Etymology. Named for living in a small stream.
Discussion. Due to the elongated idiosoma (e.g., dorsal shield L/W> 1.5), the broad frontal platelets (L/W 1.5–1.9), dorsal shoulder plates swollen anteriorly, relatively long suture line of Cx-2+3 (L 100 μm) and a moderately elongated genital field (L/W ratio 1.3–1.4), Monatractides rivulus sp. nov. can be easily distinguished from the other members of the M. macroporus species-complex.
Distribution. New Guinea (West Papua province); only known from the locus typicus (Fig. 9B).
description: Published as part of Pešić, Vladimir & Smit, Harry, 2012, Second contribution to the knowledge of water mites of the genus Monatractides K. Viets (Acari: Hydrachnidia, Torrenticolidae) from New Guinea, with descriptions of three new species, pp. 46-57 in Zootaxa 3350 on page 55, DOI: 10.5281/zenodo.281539