Monatractides (Monatractides) fontinalis, Pešić, Vladimir & Smit, Harry, 2012

Pešić, Vladimir & Smit, Harry, 2012, Water mites of the genus Monatractides (Acari: Hydrachnidia, Torrenticolidae) from Australia, with descriptions of four new species, Zootaxa 3248, pp. 1-24 : 20-23

Monatractides (Monatractides) fontinalis sp. nov.

( Figs. 12–13 )

Type material. Holotype male, dissected and slide mounted, Northern Terrıtory, small springs 4 km W of Jim Jim Falls, Kakadu NP, 23.vii.1994 ( NTM). Paratype: one female, same data as holotype, dissected and slide mounted ( NTM).

Diagnosis. Idiosoma L <600 in males, <650 in females; area of primary sclerotization of the dorsal plate with four dorsoglandularia; suture of Cx-4 partly distinct; genital field relatively large (L ratio genital field/idiosoma 0.23–0.26); postgenital area short; excretory pore in a medioposterior identation of primary sclerotization, Vgl–2 posterior to excretory pore; distal margins of P-2 and -3 without denticles, P-4 with small denticle near the insertion of the ventral hairs; I-L-6 relatively stout (L/H ratio 2.6).

Description. Male: Idiosoma (ventral view: Fig. 12B ) L 588, W 409; dorsal shield ( Fig. 12A ) L 488, W 359, L/W ratio 1.36; dorsal plate 463; shoulder plate L 134–141, W 43–44, L/W ratio 3.07–3.3; frontal plate L 98–103, W 40–42, L/W ratio 2.42–2.45; shoulder/frontal plate L ratio 1.36–1.37; capitular bay L 147, W 56, L/W ratio 2.63; Cx-1 total L 253, Cx-1 medial L 106, Cx-2+3 medial 52; ratio Cx-1 L/Cx-2+3 medial L 4.87; Cx-1 medial L/ Cx-2+3 medial L 2.94; genital field L/W 137/114, L/W ratio 1.2; ejaculatory complex normal in shape, L 172; distance genital field–excretory pore 94, genital field–caudal idiosoma margin 144; capitulum ventral L 166; chelicera total L 202; palp: total L 172 dL: P-1, 23; P-2, 52; P-3, 33; P-4, 47; P-5, 15; P-2/P-4 ratio 1.1; palp as in female; L I-4-6: 86, 85, 74.

Female: Idiosoma (ventral view: Fig. 13B ) L 619, W 442; dorsal shield ( Fig. 13A ) L 523, W 359, L/W ratio 1.46; dorsal plate 500; shoulder plate L 141–142, W 45–47, L/W ratio 3.0–3.1; frontal plate L 101–102, W 43–44, L/W ratio 2.32–2.35; shoulder/frontal plate L ratio 1.39–1.4; capitular bay L 148, W 48, L/W ratio 3.06; Cx-1 total L 244, Cx-1 medial L 95, Cx-2+3 medial 41; ratio Cx-1 L/Cx-2+3 medial L 6.0; Cx-1 medial L/Cx-2+3 medial L 2.3; genital field L/W 158/146, L/W ratio 1.08; distance genital field–excretory pore 104, genital field–caudal idiosoma margin 172; capitulum ( Fig. 13E ) ventral L 176; chelicera total L 232; palp ( Fig. 13D ): total L 181, dL: P-1, 26; P-2, 56; P-3, 37; P-4, 45; P-5,17; P-2/P-4 ratio 1.23; L I-4-6 ( Fig. 13C ): 91. 91, 92; I-L-6 L/H ratio 2.62.

Discussion. Monatractides fontinalis sp. nov. is rather similar to M. harveyi sp. nov. (see above) in the general shape of genital field and palp, but differs in minor idiosoma and gnathosoma dimensions (e.g., idiosoma L <600 in males, <650 in females, palp total L <190 vs. idiosoma L> 650 in males,> 750 in females, palp total L> 200 in M. harveyi ) and in the partly distinct posterior suture line of Cx- 4 in both sexes (indistinct in M. harveyi ). Furthermore, males of M. fontinalis sp. nov. differ in the excretory pore not embedded in the area of primary sclerotization, the relatively more extended postgenital area (24–25 % of the total idiosoma L) and the relatively shorter ejaculatory complex (L <180 μm). Females can be distinguished by the relatively larger extension of the genital field.

Etymology. Named for its occurrence in a spring.

Distribution. Australia: Northern Territory (present study).

Figures

FIGURE 12 A – B. Monatractides fontinalis sp. nov., male, small springs 4 km W of Jim Jim Falls (NT): A = dorsal shield; B = ventral shield. Scale bar = 100 μm.

FIGURE 13 A – E. Monatractides fontinalis sp. nov., female, small springs 4 km W of Jim Jim Falls (NT): A = dorsal shield; B = ventral shield; C = I-L- 5 - 6; D = palp, medial view; E = capitulum and chelicera. Scale bars = 100 μm.