Monatractides sentanicus, Pešić, Vladimir & Smit, Harry, 2011

Pešić, Vladimir & Smit, Harry, 2011, Water mites of the genus Monatractides Viets (Acari: Hydrachnidia, Torrenticolidae) from New Guinea, with descriptions of nine new species, Zootaxa 2779, pp. 39-62 : 48-50

Monatractides sentanicus sp. nov

( Fig. 10 )

Type series. Holotype, female, dissected and slide mounted, Indonesia, New Guinea, Papua Province, River Pos 7, Sentani, 9.iii.2010, 2˚ 33.740 S 140˚ 30.784 E, 103 m asl.

Diagnosis (Male unknown). Idiosoma elongated (dorsal shield L/W 1.7); the area of primary sclerotization of the dorsal and ventral plate (= dorsal and ventral plate sensu Wiles 1997b) extending almost to the posterior margin of the dorsal or ventral shield respectively; ventral margin of P-2 and -3 with straight stout seta, P-4 with well developed denticles near the insertion of the ventral hairs; genital field pentagonal; excretory pore incorporated into primary sclerotization of the ventral shield.

Description. Female: Idiosoma (ventral view: Fig. 10B ) L 666, W 444; dorsal shield ( Fig. 10A ) L 584, W 344, L/W ratio 1.7; dorsal plate 556; shoulder plate L 178, W 57, L/W ratio 3.1; frontal plate L 106, W 44, L/W ratio 2.4; shoulder/frontal plate L ratio 1.68; capitular bay L 147, W 78, L/W ratio 1.9; Cx-1 total L 250, Cx-1 medial L 103, Cx-2+3 medial 25; ratio Cx-1 L/Cx-2+3 medial L 10.0; Cx-1 medial L/Cx-2+3 medial L 4.1; genital field L/ W 143/128, L/W ratio 1.12; distance genital field–excretory pore 137, genital field–caudal idiosoma margin 247; capitulum ( Fig. 10F ) ventral L 185; chelicera L 249; palp ( Figs. 10D – E ) total L 209, dL and %L (in parentheses): P-1 29 (13.9), P-2 59 (28.2), P-3 38 (18.2), P-4 55 (26.3), P-5 28 (13.4); L P-2/P-4 ratio, 1.07; straight stout seta on ventral P-2 and -3; L I-L-4-6 ( Fig. 10C ): 78, 95, 103.

Male: unknown.

Etymology. The species is named after the area where it was collected.

Discussion. Due to the similar shape of the palp, narrow frontal platelets and shoulder dorsal plates which are not swollen anteriorly, the new species from New Guinea resembles M. neoapratima ( Wiles, 1991) , known from Malaysia and Thailand ( Wiles 1991, Pešiċ & Smit 2009). Monatractides sentanicus sp. nov. can be easily distinguished from the latter species by the following features: the area of primary sclerotization extending almost to the posterior margin of the dorsal or ventral shield respectively, excretory pore incorporated into primary sclerotization of the ventral shield and the genital field which is pentagonal in shape.

Distribution. New Guinea.

Figures

FIGURE 10 A – F. Monatractides sentanicus sp. nov., female: A = dorsal shield; B = ventral shield; C = I-L- 5 and - 6; D = palp, lateral view; E = palp, medial view; F = capitulum and chelicera. Scale bars = 100 µm.