The described male and female have an abdomen mottled greyish brown and beige.
The described male has a dark reddish-brown head and thorax; these are reddish brown in the described female. The legs of both have darker rings.
Male Austrarchaea binfordae have the highest point of the head near its posterior margin. In the described female it lies around the posterior third, with the surface sloping behind it. Similar colours accompany different head profiles.
The 2011 revision compared confirmed lowland material with two tentatively identified juveniles collected from elevated leaf litter in Nothofagus rainforest on Mount Banda Banda, Willi Willi National Park, at 1,045 metres.
The juveniles were considered possible members of the species, but their mitochondrial sequences were divergent. The authors raised possible speciation, leaving their relationship to the confirmed lowland spiders as a question for further comparison.
An extinction-risk assessment has not been added yet.
The 2011 authors identified potential threats from clearing, habitat degradation, fire and climate change at the confirmed Kerewong and Lorne State Forest populations, noting the historical forestry impacts on southeastern lowland rainforest. Repeated surveys at confirmed lowland sites could track habitat and occurrence.