The species can be distinguished by the existence of a triangular lobe on the palpal bulb on the male and the way that the copulatory openings are close to the rear of the epigyne on the female.

Rafalus desertus is a jumping spider that was first described by Wanda Wesołowska and Antonius van Harten in 2010.

[8] It was placed in the subtribe Aelurillina in the tribe Aelurillini, both named after the genus, by Wayne Maddison in 2015.

The spinnerets and pedipalps are light while the legs are spotty and between dark yellow and orange in colour.

The tegulum has a complex shape, being large and convex with a distinctive small triangular lobe at it edge.

The abdomen is similar in colour but has three darker spots and has white hairs and brown bristles.

[6] The male can be distinguished from other species by the striped pattern and the triangular lobe on the palpal bulb.

[3] The female is best differentiated by looking at the copulatory openings, which are close to the rear of the epigyne unlike most spiders in the genus.