Monatractides parviventris (K. Viets, 1935 )

Pešić, Vladimir & Smit, Harry, 2014, Torrenticolid water mites (Acari: Hydrachnidia: Torrenticolidae) from Malaysian Borneo, Zootaxa 3840 (1), pp. 1-72 : 50-51

Monatractides parviventris (K. Viets, 1935)

( Figs. 28C–D , 29C–D , Tab. 5 )

Atractides parviventris K. Viets 1935: 574 .

Material examined. Malaysia, Borneo : unnamed stream Bansadon Trail , Inobong , Crocker Range , 5º51.456 N, 116º68.403 E, alt. 436 m asl., 18.ix.2012 Smit 4/1/0 (1/1/0 mounted); Kibamabangan River , Crocker Range, 5º51.280 N, 116º08.417 E, 433 m asl., 18.ix.2012 Smit 1/1/0; Mahua stream, Mahua, Crocker Range, 5º47.838 N, 116º24.510 E, alt. 1052 m asl., 21.ix.2012 Smit 1/2/2; Mahua stream, upstream, Crocker Range, 5º47.939 N, 116º24.317 E, alt. 1050 m asl., 21.ix.2012 Smit 2/1/0 (dorsal shield of female mounted); small stream waterfall trail Inobong, 5º51.306 N, 116º08.292 E, alt. 482 m asl., 19.ix.2012 Smit 2/0/0; Kipungit River , Poring Hot Springs, Mt Kinabalu , 6º02.776 N, 116º41.432 E, 568 m asl., 15.ix.2012 Smit 2/11/0; stream Kemantis, Sayap, Mt Kinabalu , 6º09.841 N, 116º33.936 E, alt. 928 m asl., 16.ix.2012 Smit1/2/0 (1/0/0 mounted); Great Lumotok stream, Mt Kinabalu , 6º09.336 N, 116º34.056 E, alt. 1087 m asl., 17.ix.2012 Smit 0/2/0; Little Lumotok stream, Sayap, Mt Kinabalu , 6º09.467 N, 116º34.027 E, alt. 1069 m asl., 17.ix.2012 Smit 8/15/2; Silau-Silau stream, upstream, Mt Kinabalu , 6º00.681 N, 116º32.417 E, alt. 1592 m asl., 11.ix.2012 Smit 0/1/0 (mounted); Liwagu River, upstream, Mt Kinabalu, 6º01.868 N, 116º32.912 E, alt. 1919 m asl., 11.ix.2012 Smit 0/1/0 .

Morphology

General features —Idiosoma roundish; shoulder plates very short, shorter than frontal plates (shoulder/frontal plate L ratio 0.7–0.8); frontal margin with flat protrusions medial to the eyes; Cxgl–4 located far anteriorly, near tips of Cx-I; gnathosomal bay U-shaped; suture line of Cx-IV distinct, originating from lateral edge of genital field and extending posteriorly beyond posterior margin of genital field ( Figs. 29C–D ); excretory pore and Vgl–2 away from the line of primary sclerotization, Vgl–2 posterior to excretory pore; gnathosoma with long dorsal apodemes; P-4 with well visible denticle near insertion of ventral setae. Male: medial margin of Cx-II/III short; genital field subrectangular; ejaculatory complex: proximal and distal arms well developed, carina anterior long, proximal chamber small. Female: genital field pentagonal, anteriorly enlarged, laterally straight, tapering posteriorly ( Fig. 29C ).

Remarks: The specimens examined from Borneo agree well in general morphology with Monatractides parviventris (K. Viets, 1935) , a species originally described from South Sumatra (K. Viets 1935) based on a single female and one deutonymph. The male was described by Lundblad (1971) from Central Java.

Wiles (1999) reported M. parviventris from several sites in the catchment area of the River Belalong in North Brunei. He mentioned variability of his specimens in the shape of the idiosoma (rounded to oval) and in the fusion between the median margins of frontal plates. We also found a mixed populations with separate ( Fig. 28C ) and fused ( Fig. 28D ) frontal plates.

As stated by Wiles (1999) the taxonomy of this species needs further investigation, probably with application of molecular techniques. However, unfortunately our effort to obtain the mtCOI fragment from specimens of this species from Borneo, was not successful (see under Molecular results).

Distribution. Sumatra (“ Atractides parviventris ” K. Viets 1935 ), Java (“ Torrenticola parviventris ” Lundblad 1971 ), Thailand ( Pešić & Smit 2009b).

Figures

FIGURE 28A–I. Photographs of dorsal shield. A–B Monatractides longiventris (K. Viets, 1939), Mahua stream: A = male; B = female. C–D M. parviventris (K. Viets, 1935): C = female, stream Bansadon Trail; D = male, Kemantis stream. E M. oxystomus (K. Viets, 1935), male, Kipungit River. F–G M. cf. macroporus (K. Viets, 1935): F = male, stream Bansadon Trail; G = female, Little Lumotok stream. H–I M. epiales n. sp., Kipungit River: H = male; I = female.

FIGURE 29A–I. Photographs of ventral shield. A–B Monatractides longiventris (K. Viets, 1939), Mahua stream: A = male; B = female. C–D M. parviventris (K. Viets, 1935): C = female, stream Bansadon Trail; D = male, Kemantis stream. E M. oxystomus (K. Viets, 1935), male, Kipungit River. F–G M. cf. macroporus (K. Viets, 1935): F = male, stream Bansadon Trail; G = female, Little Lumotok stream. H–I M. epiales n. sp., Kipungit River: H = male; I = female.