These specimens were found in the first layers of soil, 3 to 5 cm deep, under large stones in a single locality in the state of Minas Gerais in Brazil.

The type specimens are deposited in the Instituto Butantan in the city of São Paulo in Brazil.

No short sclerite is visible in front of the main sternite of the ultimate leg-bearing segment, and this presternite is apparently absent.

The main sternite of the ultimate leg-bearing segment is wider than long, with a length/width ratio ranging from 0.7 to 0.8.

Furthermore, in both of these species, the cephalic plate is longer than wide and lacks a transverse suture, the forcipular pretergite is exposed, the first article of the forcipule is longer than the ultimate article, and the sternite of the ultimate leg-bearing segment is wider than long.

Furthermore, the denticle on the ultimate article of the forcipule is sharp and strikingly large in A. acutus but small in A. pereirai.