The male differs from the similar Langona bitumorata by the single bump on its palpal bulb.

Langona mediocris is a jumping spider first described by the Polish arachnologist Wanda Wesołowska in 2000.

[5] It is particularly closely related to the genus Aelurillus, after which the subtribe, tribe and group are named.

The different Langona species generally cannot be distinguished from each other or from other members of the group by either their colours or the patterns that appear on their bodies, but by the structure of the copulatory organs.

It is brown-black with two converging lines of white hairs running from the back of the eyes all the way to the end of the carapace.

The palpal bulb is bulbous and has a thin and hairy appendage, or apophysis, on the tibia that is relatively long.

[9] The male closely resembles the related Langona bitumorata, but can be distinguished by the single bump on the palpal bulb.