HYGROBATIDAE Koch, 1842

Wiles, P. R., 2004, Water mites (Acari: Hydrachnidia) from South-East Asia, Thailand and Sulawesi Tenggara (Indonesia): descriptions of new species and new records, Journal of Natural History 38 (17), pp. 2153-2165 : 2158-2159

Family HYGROBATIDAE Koch, 1842 Hygrobates projectus Wiles, 1990 ( figure 4 )

Material examined. HOLOTYPE: „, S205„, 3 November 1985, small stream, Tangkoko , Sulawesi Utara . PARATYPE 1: S212”, PARATYPE 2: S215„, PARATYPE 3: S219”, PARATYPE 4: S204„. S88”, S90„, 8 November 1985, River Toraut, Domoga Bone , Sulawesi Utara. S358”, S352„ S403” 27 July 1999, S. Lamotome, small gravel stream, Buton.

Description. Male: body length 528, width 326. Dorsum striate, without plates; A1 setae large. Infracapitulum length 173. Glandularium E2 behind suture line EpIII/IV; E4 located posterior to EpIV. Fused genital plates, each with three acetabula in a triangular arrangement, with two posterior acetabula located adjacent to each other behind the genital pore; length genital pore 59, width 24, width genital field 139. Pedipalp of typical proportions with a short denticulate ventral projection on P2, ventral denticles (~papillae sensu, Cook, 1986) on the anterior half of P3 and ventral setae on P4 located in the middle of the segment; length PI –PV 23, 72, 46, 91, 35. Swimming setae absent. Length I-Leg-3–6 66, 101, 100, 102; II-Leg-3–6 70, 108, 115, 115; III-Leg-3–6 77, 123, 139, 111; IV-Leg-3–6 101, 150, 160, 139.

Female: body length variable, 443, width 383. Dorsum striate, without plates. Infracapitulum length 191. Epimera as in male. Genital plates, each with three acetabula in a triangular arrangement, with the posterior two acetabula adjacent to each other, shorter than genital pore; length genital pore 125; length genital plate 83, width 52; width of pregenital sclerite 63. Pedipalp length PI –PV 24, 80, 48, 98, 39. Swimming setae absent. Length I-Leg-3–6 69, 104, 111, 108; II-Leg-3–6 73, 118, 122, 122; III-Leg-3–6 87, 132, 150, 136; IV-Leg-3–6 108,

160, 167, 153.

Remarks. Hygrobates projectus was not described by Wiles (1990) from North Sulawesi (Sulawesi Utara) but listed as a nomen nudum in table 2, p. 282. It is here described for the first time. Hygrobates projectus is similar to H. limi , H. australicus and H. orientalis . Unfortunately, males have not been described for H. australicus but the long anterior genital sclerite of female H. australicus is diagnostic (w 75% of the length of the genital pore compared to v 50% in H. projectus , H. orientalis and H. limi ). The distribution of denticles on P2 separates H. orientalis (apical one-third) from H. projectus (distal two-thirds). Hygrobates limi has short sutures EpIII/IV that terminate at the glandularium E4 whilst H. projectus has an almost complete suture nearly reaching the medial margin of the posterior pair of epimera.

Figures

FIG. 4. Hygrobates projectus Wiles, 1990. (a) Venter „; (b) pedipalp „; (c) venter ”. Scale bar: 100 Mm (a, b); 62.5 Mm (c).