Peloribates szirakii, Mahunka, 2008

Mahunka, S., 2008, A New Genus And Some Other Data Of Oribatids From Thailand (Acari: Oribatida), Acta Zoologica Academiae Scientiarum Hungaricae 54 (2), pp. 125-150 : 143-146

Peloribates szirakii sp. n.

( Figs 44–46 )

Diagnosis: Rostrum wide, rounded. Lamellae short, but well developed, bearing conspicuously long lamellar setae being much longer than the interlamellar ones. Sensillus long directed outwards or backwards, its head comparatively large, fusiform. Notogastral and pteromorphal surface well foveolate. Fourteen pairs of nearly equal, setiform, well barbed notogastral setae present. Four pairs of simple sacculi hardly observable. Epimeral setae setiform, thin, mostly ciliate. Custodium conspicuously long, sharply pointed, directed inwards. Genito-anal setal formula: 5–1–2–3. Anal setae short, posterior adanal ones (setae ad 1) much thicker than other anal or adanal setae. All legs tridactylous.

Material examined: Holotype: Thailand, Province Prachin Buri, Sakaerat Research Station . 02.06.2001. Leg. E. HORVÁTH & GY . SZIRÁKI (As-798). Four paratypes from the same sample. Holotype (1744-HO-2007) and three paratypes (1744-PO-2007): HNHM , one paratype: MHNG .

Measurements: Length of body: 370–390 µm, width of body: 263–289 µm.

Prodorsum: Wide, its apex rounded. Prodorsal surface rarely foveolate. Lamellae short, bearing conspicuously long lamellar setae being much longer than the rostral or interlamellar ones. Rostral setae distinctly, lamellar and interlamellar ones sparsely ciliate. Peduncule of the sensillus very long, its head fusiform, rounded distally, slightly ciliate ( Fig. 44 ).

Notogaster: Dorsosejugal suture distinct, convex. Notogastral surface ornamented by small foveolae, the distance among them much greater than the diameter of the foveolae. Fourteen pairs of long, well ciliate, setiform notogastral setae ( Fig. 44 ) and four pairs of small sacculi present. prodorsum in dorsal view

Lateral part of podosoma: Rostrum beak shaped in lateral view. Prelamella long, well developed, however, not reaching the rostral margin ( Fig. 46 ). Tutorium very long, with sharply pointed apex and dilated basal part. Rostral setae arising at the apex.

Ventral parts ( Fig. 45 ): Infracapitulum and the anterolateral part of the epimeral region foveolate, behind it, the 2nd epimeral surface punctate; 3rd and 4th epimeral surfaces also foveolate. Apodemata and epimeral borders mostly well developed, long. Epimeral setae setiform, comparatively long, thin, but mostly well ciliate. Discidium large, custodium with very long, thin distal process, directed inwards. Circumpedal carina long, reaching the lateral margin of ventral plate. Surface of genital plates ornamented by longitudinal scratches. Five pairs of short, thin genital setae present. Ventral plate ornamented by larger foveolae, but the areas among them punctate. Surface of anal plates irregularly punctate, anal setae short, fine. Adanal setae longer than anal setae, among them setae ad 1 longest, setae ad 3, shortest of all, all well ciliate.

Legs: All legs triheterodactylous. Femur II and trochanter and femur of leg IV well foveolate. Femur II with projecting anteroventral part.

Remarks: The new species is well distinguishable from the heretofore known Peloribates species by the long lamellar setae, the form of the sensillus, the ratio of the adanal setae and especially by the long and spiniform custodium.

Etymology: I dedicate to Dr. GY. SZIRÁKI, the renowned neuropterologist of the Hungarian Natural History Museum, who helped to collect this material in Thailand, and also in some other collecting trip in the tropical regions.

Figures

Figs 44–46. Peloribates szirakii sp. n. – 44 = body in dorsal view, 45 = body in ventral view, 46 = rostral part of prodorsum in lateral view