Monatractides

Pešić, Vladimir & Smit, Harry, 2014, Torrenticolid water mites (Acari: Hydrachnidia: Torrenticolidae) from Ghana, Zootaxa 3820 (1), pp. 1-80 : 71

Monatractides sp. 2

( Figs. 48A–F , 49C–E )

Material examined. Ghana: Kintampo Falls, 8º 05.413 N, 1º 41.881 W, 3.iii.2011, Smit, 1/0/0 (mounted).

Morphology. Male. General features —Idiosoma roundish; frontal platelets broad (L/W ratio 1.8), shorter than frontal platelets (shoulder/frontal platelets L ratio 1.1.–1.2); medial margin with a flat protrusion medial to the eyes ( Fig. 48A ); Cxgl–4 located far anteriorly, near tips of Cx-I; gnathosomal bay moderately deep, U-shaped; medial margin of Cx-II/III relatively short; genital field subrectangular; suture line of Cx-IV nearly obliterated; excretory pore away from the line of primary sclerotization and on the same level as Vgl–2; Palp: ventral seta on P-4 short ( Fig. 48F ); IV-L-2–5 distally swollen and with bluntly pointed sheaths covering the base of the following segment, IV-L-6 ventral and dorsal margin distally strongly diverging ( Fig. 48E ).

Measurements. Idiosoma (ventral view: Figs. 48C , 49D ) L 589, W 447; dorsal shield ( Figs. 48B , 49C ) L 473, W 381, L/W ratio 1.24; dorsal plate L 413; shoulder platelets L 128–138, W 63–66, L/W ratio 2.0–2.2; frontal platelets L 112–119, W 63–66, L/W ratio 1.8; shoulder/frontal platelets L ratio 1.08–1.22. Gnathosomal bay L 112, Cx-I total L 217, Cx-I mL 105, Cx-II+III mL 58; ratio Cx-I L/Cx-II+III mL 3.7; Cx-I mL/Cx-II+III mL 1.8. Genital field L/W 109/97–98, ratio 1.12; distance genital field-excretory pore 163, genital field-caudal idiosoma margin 203. Gnathosoma vL 139; chelicera total L 150; palp total L 166, dL/H, dL/H ratio: P-1, 24/18–19, 1.29; P-2, 45/ 33, 1.37; P-3, 31/27, 1.15; P-4, 43/18, 2.37; P-5, 23/9, 2.5; P-2/P-4 ratio 1.05; dL of I-L-3–6: 62, 85, 92, 98; I-L-6 H 38–39, dL/H I-L-6 ratio 2.5.

Discussion. The combination of relatively stout dorsal shield with broad frontal platelets ( Figs. 48B , 49C ), a box-shaped gnathosomal bay, the relatively small genital field, the nearly obliterated suture line of Cx-IV ( Figs. 48C , 49D ), I-L-6 distally slightly thickened ( Fig. 48D ) and IV-L-2–5 thickened distally with bluntly pointed sheaths covering articulation of the following segment ( Fig. 48E ), easily separates the single male from Kintampo falls from all other Monatractides species from Ghana. Most probably we are dealing with an undescribed species, but since larger material is not available, a final decision can not be made.

Remarks. The male ejaculatory complex was not found but sclerotized framework immediately above the genital field can be hardly visible ( Fig. 49E ).

Figures

FIGURE 48 A – F. Monatractides sp. 2, male, Kintampo Falls: A = frontal margin of idiosoma, dorsal view; B = dorsal shield; C = idiosoma, ventral view; D = I-L- 5 and - 6; E = IV-L; F = palp, lateral view. Scale bars = 100 Μm.

FIGURE 49 A – E. Photographs of: A – B Monatractides sp. 1, male, Apkonu stream: A = dorsal shield; B = idiosoma, ventral view. C – E Monatractides sp. 2, male, Kintampo Falls: C = dorsal shield; D = idiosoma, ventral view; E = inner side of genital field (arrow showing ejaculatory complex reduced to sclerotized framework).