[1][2] Armadilliidum petralonense was described as a distinct species of Armadillidium in 2008, based on specimens collected as far back as 1960.

The species is also thought to belong to the "Armadillidium fossuligerum complex", a group of 4 species (A. jerenntrupi, A. fossuligerum sensu lato, A. petralonense and A. pieperi) that occur in the southern part of the Balkan Peninsula (mainly Greece and the adjacent areas of North Macedonia and Bulgaria).

The coloration of the body consists of grey tergites, decorated with small yellow spots at the attachment sites of the thoracic muscles, and yellowish-grey epimera.

The frontal shield surpasses the anterior edge of the head, has a completely rounded upper margin and lacks lateral angles.

Specifically, specimens have been collected from the eastern suburb of Panorama, near the city of Thessaloniki, in the former region and from the towns of Galatista and Petralona in the latter.