Austrarchaea thompsoni Rix & Harvey 2012

Austrarchaea thompsoni is a species of spider in the family Archaeidae. It is endemic to Australia.

Holotype male: Total length 2.97; leg I femur 3.23; F1/CL ratio 2.74. Cephalothorax dark reddish-brown; legs tan-brown with darker annulations; abdomen mottled grey-brown and beige, with darker brown dorsal scute and sclerites (Fig. 10A). Carapace tall (CH/CL ratio 2.13); 1.18 long, 2.51 high, 1.13 wide, ‘neck’ 0.63 wide; bearing two pairs of rudimentary horns; highest point of pars cephalica (HPC) near posterior third of ‘head’ (ratio of HPC to post-ocular length 0.69), carapace gently sloping posterior to HPC; ‘head’ not strongly elevated dorsally (post-ocular ratio 0.25). Chelicerae with short brush of accessory setae on anterior face of paturon (Fig. 10B). Abdomen 1.64 long, 1.23 wide; with two pairs of dorsal hump-like tubercles (HT 1-4); dorsal scute fused anteriorly to epigastric sclerites, extending posteriorly to first pair of hump-like tubercles; HT 3-4 each covered by separate dorsal sclerites. Unexpanded pedipalp (Figs 10C–E) of Type A morphology (Fig. 6), with large, retrolaterally directed, arched conductor; embolus distally directed, slightly sinuous, with short triangular spur situated near base of exposed embolic portion, embolus projecting beyond distal rim of conductor by slightly less than 1/2 length of exposed embolic portion; tegular sclerite 3 (TS 3) short, spur-like, with constricted tegular base and sharply pointed, claw-like apex; TS 2-2a looped beneath overhanging retrolateral edge of conductor, TS 2 with rounded, subtriangular apex, TS 2a projecting beyond distal rim of conductor to near tip of embolus; TS 1 very small, obscured by TS 2-3, not visible in ventral view. Female: Unknown.

Austrarchaea thompsoni is known only from Devils Thumb, on the Carbine Tableland 10 km west-north-west of Mossman (Figs 19, 25). The single known specimen was collected in high altitude tropical rainforest.