Hydrachna hamata Lundblad, 1947

Smit, Harry, 2014, Australian water mites of the genus Hydrachna Müller, with the description of five new species (Acari: Hydrachnidia: Hydrachnidae), Zootaxa 3827 (2), pp. 170-186 : 174-176

Hydrachna hamata Lundblad, 1947

( Figs. 5A–C )

Material examined. Victoria. 5/2/0, Victoria Lagoon, SW of Grampians NP, 30-ix-1997. Tasmania. 1/1/0, Temporary pond 2 km W of Musselroe Bay, Mt Williams NP, 20-x-1997. South Australia. 2/1/0, Hacks Lagoon (behind reed bed), Bool Lagoon Game Reserve, 13-x-2001.

Description. Male: See Lundblad (1947). L/W of the specimens from this study: 2432–3196/ 2010–2995.

Female: Idiosoma L/W 3015/2593 (2834–3960/2613–3598). Dorsum as in male. Fourth coxae posteromedially not very far extending, with a relatively short secondary sclerotization. First, third and fourth coxae with one seta. Genital field 502 long and 842 wide, indented anteriorly for approximately 2/3, with very numerous acetabula. Central part of genital plate with nine small setae. Length of PI–PV: 300, 300, 332, 146, 81; PIV stocky, contracted anteriorly, L/H 2.19. Chelicera 1588 long. Length of I-leg-4–6: 365, 360, 429. Length of IVleg-4–6: 875, 794, 437.

Remarks. The female has not been described before. The female is characterized by the large genital field with very numerous small acetabula and a stocky PIV. Previously the species has been reported from Victoria only.

Figures

FIGURE 5. A – C. Hydrachna hamata Lundblad, female. A = coxal and genital area; B = palp and capitulum; C = palp. Scale bars: A – C = 200 µm.