The paratype specimen for the species, A. johnsoni, is recorded to have a total length of 43 mm and a width of 38 mm, while the type specimens of A. sulcata is noted to have been up to 45 mm in length and 25 mm in width if complete.
Measurements for the species A. johnsoni are provided with a holotype measuring 43 mm in length and 38 mm in width, while type specimens of A. sulcata have been recorded as being up to 45 mm long and 25 mm wide if complete.