The abdomen has a distinctive pattern with a white stripe to the front, dark shape in the middle and orange marks on the sides, after which it is named.

Mexcala signata is a jumping spider that was first described by the Polish arachnologist Wanda Wesołowska in 2009, one of over 500 species she identified during her career.

[2][3] The genus was a member of the tribe Heliophaninae alongside Pseudicius and Cosmophasis, which was absorbed into Chrysillini by Wayne Maddison in 2015.

[7] The species itself has a name that is derived from the Latin word for signed and relates to the pattern on the spider's abdomen.

[9] The female has a dark carapace covered in delicate light hairs that is typically 3.2 mm (0.13 in) long.

The epigyne is plain with indistinct copulatory openings placed horizontally with sclerotized edges that lead to short seminal ducts and bean-shaped receptacles.

[14] The chelicerae have short thick spines on them which may be used for digging holes to act as underground hiding places.