The male and female have a dark reddish-brown head and thorax.
The legs have darker rings, and the abdomen is mottled greyish brown and beige.
Male and female Austrarchaea hoskini differ in the hairs on the front of their long jaws. The described male has a short brush, while the female lacks those accessory hairs. Small structures differ between the otherwise similarly coloured sexes.
The 2012 study compared male reproductive appendages near the mouth among the related spiders of north-eastern Queensland. Standardised drawings viewed from the same direction and at the same scale were arranged into five structural types. This species represents one of those types.
Its appendage contains a large dagger-shaped plate and a rounded, fin-like projection. Other slender parts loop into a figure-of-eight shape in ventral view. Their shapes and orientations together help distinguish the species. The approximately three-millimetre male contains intricate structures that microscopy can reveal.
An extinction-risk assessment has not been added yet.
The 2012 authors considered information insufficient to assess this species’ conservation status. Its recorded locality, Mount Elliot, lies in Bowling Green Bay National Park. The parks authority asks visitors to clean vehicles, footwear and outdoor equipment before arriving to prevent introductions of weeds, insect pests and soil pathogens. Alongside these park-wide measures, examining rainforest condition and spider occurrence around historical localities could inform conservation.