Unionicola (Giselatax) uncatiseta, Smit, Harry, 2008

Smit, Harry, 2008, Australian Unionicola (Acari: Hydrachnidia: Unionicolidae), with the description of two new subgenera and eight new species, Zootaxa 1674, pp. 1-26 : 12-13

Unionicola (Giselatax) uncatiseta n. sp.

( Figs. 12–18 )

Material examined. Holotype male, Western part Deep Reach Pool, Millstream-Chichester NP, Western Australia, Australia, 16 August 1994 ( WAM). Paratypes: Western Australia: 1 male, 13 females, same data as holotype ( WAM); 4 males, 23 females, Fortescue Falls (pools), Hamersley Range NP, Western Australia, Australia, 22° 28’39.18 “S 118° 33’3.04” E, 11 August 1994 ( WAM). Northern Territory: 13 females, 1 male, 1 nymph, same data as holotype ( NTM); 1 male, 3 females, pool near Jim Jim Falls, Kakadu NP, 23 July 1994 ( NTM); 4 males, 13 females, pools upstream of Waterfall Creek, Kakadu NP, 13° 25.762 S 132° 25.089 E, 25 July 1994 ( ZMAN); 1 male, 9 females, 2 nymphs, plunge pool Barramundie Creek, Kakadu NP, 13° 19’07.56”S 132° 26’16.61´E, 24 July 1994 ( NTM); 2 males, 13 females, Plunge pool Edith Falls, Katherine Gorge NP (= Nitmiluk NP), 14° 10.899 S 132° 11.342 E, 30 July 1994 ( ZMAN); same location, 3 males, 5 females, 2 October 2005 ( ZMAN); 1 male, Florence Creek downstream of Florence Falls, Litchfield NP, Northern Territory, 13° 0 5.885 S 130° 46.999 E, 25 September 2005 ( NTM); 1 male, Walker Creek, Litchfield NP, 13° 0 4.694 S 130° 41.929 E, 25 September 2005 ( NTM).

Other material. Western Australia: 4 females, Pond Dales Gorge, Hamersley Range NP, 22° 28’37.53’’ S 118° 33’26.66’’ E, 12 August 1994; 6 females, Pond Knox Gorge, Hamersley Range NP, 22° 22’12.39” S 118° 17’51.81”E, 13 August 1994; 3 males, 8 females, 3 nymphs, pond Kalamina Gorge near falls, Hamersley Range NP, 22° 24’48.08” S 118° 24’34.50” E, 13 August 1994; 1 male, 3 females, Chinderwariner Pool, Millstream-Chichester NP, 21° 35’32.34” S 117° 4’8.55” E, 15 August 1994; 1 male, 6 females, 5 nymphs, Palm Pool, Millstream-Chichester NP, 21° 34’2.85”S 117° 2’32.10”E, 15 August 1994; 2 males, 2 females, pool Lennard Gorge, The Kimberley, 10 September 1998; 4 males, 14 females, plunge pool Adcock Gorge, The Kimberley, 12 September 1998; 6 males, 17 females, pool Manning Gorge Falls, The Kimberley, 13 September 1998; 2 males, 35 females, Miners’s Pool, Drysdale River Homestead, The Kimberley, 14 September 1998; 1 male, 4 females, Jackeroo’s Waterhole, El Questro Station, The Kimberley, 15 September 1998. Northern Territory: 1 male, 1 female, billabong Yellow Waters, Kakadu NP, 21 July 1994; 1 male, 3 females, Mardugal Billabong, Kakadu NP, 21 July 1994; 3 males, 8 females, Jim Jim Billabong at crossing with Kakadu Highway, Kakadu NP, 22 July 1994; 2 males, 5 females, pond in Jim Jim Creek, at Jim Jim Crossing, Kakadu NP, 22 July 1994; 1 male, 3 females, pool near Jim Jim Falls, Kakadu NP, 23 July 1994; 6 males, 2 females, 1 nymph, Barramundie Creek, Kakadu NP, 24 July 1994; 6 males, 35 females, pools Waterfall Creek, upstream of falls, Kakadu NP, 13° 25.762 S 132° 25.089 E, 1 October 2005.

Diagnosis. IV-leg-4 of male with three specialized large setae: one hook-like seta, one slightly bowed seta and one double-toothed seta.

Description. Male: Body soft, idiosoma 486 (446–559) long and 304 (251–356) wide. Most setae accompanying dorsal glandularia very long. Apodemes of anterior coxal plates extending well beyond anterior margin of third coxal plates. A pair of glandularia incorporated into sclerotisation of posteromedial corners of fourth coxal plates. Accompanying setae of these glandularia long. Fourth coxal plates with short posterior projections. Genital field terminal with five pairs of acetabula, the two anterior pairs somewhat distanced from the three posterior pairs. Genital field located terminal, genital plates not fused ventrally. A pair of large glandularia tubercles lateral of genital field. Lengths of PI-PV: 8, 108, 34, 86, 64. Peg-bearing tubercle of PIV much shorter than longest tubercle, PIV stocky, PV slender. Lengths of I-leg-4-6: 259, 215, 223. I-leg-6 bowed, segments 3–5 of first leg with long, fluted setae, those of second and third segment on long tubercles. I-leg-6 posteroventrally with an enlarged, slightly bowed seta, which is shorter than the claw. Lengths of IVleg-4-6: 130, 421, 332. IV-leg-4 stocky, with three large, specialized setae: one hook-like seta, one slightly bowed seta and one double-toothed seta. IV-leg-5 and -6 long and slender. Second and third leg with long, stiff setae which probably act as swimming setae. IV-leg-4 with two long and two short swimming setae.

Female: Idiosoma soft, 729 (608–844) long and 470 (413–584) wide. Most setae accompanying dorsal glandularia very long. Apodemes of anterior coxal plates extending well beyond anterior margin of third coxal plates. A pair of glandularia incorporated into sclerotisation of posteromedial corners of fourth coxal plates; accompanying setae of these glandularia long. Fourth coxal plates with short posterior projections. Genital field terminal with four genital plates and five pairs of acetabula, each anterior plate with two acetabula, each posterior plate with three acetabula. Anterior genital plates each with two enlarged setae, posterior genital plate with one enlarged seta. Lengths of PI-PV: 14, 140, 62, 130, 100; palp as in male. Lengths of I-leg-4-6: 381, 284, 284; I-leg-6 bowed, fluted setae long, papillae more conspicuous than in male; claws compared to claws of other legs somewhat stocky. I-leg-6 posteroventrally with an enlarged, slightly bowed seta, which is shorter than the claw. Lengths of IV-leg-4-6: 332, 514, 417. All legs with small claws with the clawlet longer than the claw, and without claw blade. Stiff swimming setae as in male present. IV-leg-4 with two and IV-leg- 5 with three more flexible and longer swimming setae.

Nymph: Idiosoma 401 long and 300 wide. Legs with less setae as adult, IV-leg-5 with three swimming setae.

Etymology. Named for the hook-like seta of IV-leg-4.

Remarks. This is the third known species of the subgenus Giselatax . The new species is well characterised by its specialized setae of IV-leg-4. The female of the new species cannot be separated from other females of the subgenus or from females belonging to other subgenera, e.g. U. longiseta .

Figures

FIGURE 12 – 18. Unionicola uncatiseta n. sp. 12, 13, 15, 16, holotype male, 12, ventral view; 13, dorsal view; 15, palp; 16, IV-leg- 4 - 6; 14, paratype male, genital field; 17 – 18, paratype female, 17, genital field; 18, palp. Scale bars = 50 µm.