Xistera barlee, Raven & Hebron & Williams, 2023

Raven, Robert J., Hebron, Wendy & Williams, Kylie, 2023, Revisions of Australian ground-hunting spiders VI: five new stripe-less miturgid genera and 48 new species (Miturgidae: Miturginae), Zootaxa 5358 (1), pp. 1-117 : 107-109

Xistera barlee sp. nov.

Figs 83–84

Diagnosis. Males differ from those of Xis. coventryi sp. nov. in the massive scoop in the RTA ( Fig. 84b ), and from Xis. auriphila sp. nov. in the bigger median apophysis with less basal incursion ( Fig. 84a ). Female unknown.

Etymology. The species epithet is a noun in apposition from the type locality.

Type Material. Western Australia: male holotype, Barlee Range Nature Reserve , site BR1 , 23°02`39”S 115°48`44”E=-23.0441°S, 115.8122°E, 15–18 Jun 1994, P.G. & G.W. Kendrick, dry pitfall trap, WAM T33413 .

Paratypes. 1 ma., Pilbara region , ca. 8 km W of Newman, 23°24’57”S, 119°35’31”E, 14 Mar–18 May 2010, pitfall trap, J. Gollan, AM KS120115 ; 2 ma., Laverton , 39 km E, 28°28’S 122°05’E, 19–22 Oct 1990, E. R. Pianka , Pitfall traps, WAM98 /700–701; 1 ma., Barlee Range , 23°04’46”S 1154727”E, 15–18 Jun 1994, P.G. & G.W. Kendrick, dry pitfall trap, WAM T33412 (97/178) ; 4 ma., same data but, 23°24’41”S 115°53’39”E, 11–14 Jun 1994, WAM T33407 (97/173–177).

Description. Male, holotype WAM T33413

Carapace 4.40 long, 3.27 wide. Opisthosoma 3.71 long, 2.63 wide. Total, 8.20.

I: 3.47, 1.54, 3.20, 3.07, 2.07, 13.35. II: 3.47, 1.47, 3.07, 3.14, 2.07, 13.22. III: 3.54, 1.54, 3.17, 3.80, 2.20, 14.25. IV, 4.60, 1.24, 4.20, 6.47, 2.67, 19.18. Palp: 1.97, 0.73, 0.87, -, 2.20, 5.77.

Colour: carapace light brown with darker lines around eyes, along caput edge, and ends of striae with 2 large triangles in diagonal retrobasal striae, and 2 paramedial. Opisthosoma dorsally dark brown with pallid spots at sigilla points and 2 large pallid spots posteriorly; venter entirely pallid; femora with 3 irregular bands of dark brown on yellow brown legs.

Carapace: light uniform pilosity. Eyes: 4 rows; rows close but separate; ALE well in front of PME. ALE smallest, other eyes of similar size. PLE look slightly back. Chelicerae: promargin with 3 teeth, retromargin with 2. Eye group, front width, back width, length, 40: 51: 41. Sizes: AME, 10; ALE, 6; PME, 10; PLE, 12. Interspaces: AME–AME, 7; AME–ALE, 6; PME–PME, 4; PME–PLE, 8. Sternum: short hairs on margin, long black bristles on submargin converge centrally; pilosity light.

Legs: Trochanteral notches shallow, ca. x 3–4 wider than deep. Claws with five long teeth. Scopula: very thin for 2/3–3/4 of metatarsi I–IV; denser but still thin on tarsi I–IV; pseudotufts almost absent. Spines: I: fe pv1p2d4r3; pa 0; ti p2r2v2.2.2 me v2. II: fe pv1p2d3r2; pa 0; ti p2r2v2.2.2; me p1. v2.1. III: fe pv1p3d3r3; pa 0; ti p2d2.1r2v2.2.2; me p1.1.1.1r2.1.1v2.1.1.1.1. IV: fe p3d3r1; pa 0; ti p2d2.1r2v2.2.2; me p1.1.1r2.1.1.2v2.1.1.1.1. Palp: fe d1.1.2; pa p1d1.1 (including 1 apical); ti p2d1.

Spinnerets: PLS and ALS long cylindrical; PLS ca. 0.5 x diameter and 0.6 x length of ALS with conical apical article; PMS smaller cylinders.

Palp: tibia with proventral keel for length, with glabrous trough to RTA which occupies most of retrolateral edge of tibia, basally two adjacent rounded prongs directed retrolaterally; distally, a scoop with concave shield and unsclerotised band, distally a long massive twisting scoop extends for half the length of cymbium with glabrous sclerotised shield opposing it on cymbium. Cymbium very asymmetrical, deeply rounded on promargin with discontinuity to apex; apical cone very short, blunt, rounded; lateral margins narrow, retrobasal with short narrow groove, overlaid by tegulum; prodistal 1/3 dorsally with distinct scopula. Median apophysis a large wide apicocentral hook with deep unsclerotised incursion; clearly free of embolus. Embolus origin central; base bipartite, separated by wide unsclerotised groove; upper a twisted kidney-like plate; lower, small trianguloid, embolus tapers quickly passing from retrobasal below subtegulum and behind median apophysis to small, transverse, apical conductor. Tegulum extends from prodistal behind median apophysis. Subtegulum large, probasal, reniform.

Distribution. Known only from Laverton and the Barlee Range Nature Reserve, Western Australia.

Figures

FIGURE 83. Xistera barlee sp. nov.: a, b, scanning electron micrographs, male palpal tibia, cymbium and bulb, ventral (a) and retrolateral (b) views; c–e, male holotype, WAM T33413: c, median apophysis, ventral view; d, habitus, dorsal view; e, RTA, retroventral view.

FIGURE 84. Xistera barlee sp. nov., male holotype, WAM T33413, palpal tibia, cymbium and bulb: ventral (a), retrolateral (b) and retroventral (c) views.