Megalobulimus popelairianus occurs in Ecuador, in Bolivia (doubtful)[2] and in Brazil.

The color of the shell is dark reddish-brown or rich chestnut with narrow darker streaks and a lighter margin below the suture.

Succeeding whorls 2, having growth-wrinkles and a dense but rather irregular spiral granulation which fades out upon last whorl, which is more coarsely sculptured by lengthwise wrinkles and has generally more or less- coarse spiral malleation.

[2] The aperture is about half the shell's length, trapezoidal, white with a livid tint within.

Outer lip is well reflexed, white (or light-brown edged), convexly curved.