Selenogyrus austini is a theraphosid spider.

[1] The specific name "austini" is in honour of the collector of the type specimens, Mr. E. E.

[1] S. austini has a characteristic crescent-shaped layout of the granules on the labium, and also has unique layout of the labio-sternal "mounds": the anterior pair being larger than in other species.

It also has relatively stout stridulatory clavate ("club-shaped" [2]) setae on the chelicerae.

The spermathecae are quite narrow at their base, and the clypeus is small but not absent.