Gretacarus bifalcisetus Smit, 1998

Orginal, Harry Smit, 2021, The water mites of Western Australia (Acari: Hydrachnidia), with the description of 13 new species, Acarologia 61 (4), pp. 928-966 : 961

Gretacarus bifalcisetus Smit, 1998

( Figures 18 A-D)

New record — 1/0/0, Fortescue River, Millstream-Chichester NP, 21°34.236′ S 117°03.276′

E, 277 m asl, 30 Jan. 2019.

Description — Male: Idiosoma yellowish, central part reddish, dorsally 551 long and 478 wide, ventrally 518 long. Dorsal shield 478 long and 401 wide, middle glandularia closer to each other than anterior and posterior pair. Dorsal shield with three pairs of areas without idiosoma pores and posteriorly an unpaired area without such pores ( Figure 18A). Suture lines of coxae incomplete and indistinct. Gonopore 76 long and 51 wide, anteriorly with a maximum of two acetabula in row, posteriorly with a maximum of three acetabula in a row. Glandularia anterolateral to gonopore not covered by flap-like extensions of Cx-IV ( Figure 18B). Excretory pore on a shallow hump. Length of P1-5: 20, 42, 30, 48, 22. P4 dorsally with a small hump, ventral with a large setal tubercle with a tooth-like seta ( Figure 18C). First leg not measured. Length of IV-leg-4-6: 90, 97, 80. IV-leg-4 anterodorsally with a stout seta, unmounted curved and blunt, mounted curved and pointed, anteromedially three stout, curved setae and anteroventrally with two large setae. IV-leg-3 stocky, with 5 long ventral setae (only two of these illustrated) and two stout anterodorsal setae. IV-leg-2 ventrally with eight long setae ( Figure 18D).

Distribution — Known from Western Australia only.

Remarks — In the original description of Smit (1998a) IV-leg-4 of the male was illustrated with two large, hyaline anteromedial curved setae, the specimen described above has three of these setae. The large ventral seta of P4 of the holotype is not tooth-like, but has a straight anterior margin.