About Amphidromus atricallosus (A.Gould, 1843)
This entry describes the shell of Amphidromus atricallosus (A.Gould, 1843). The shell reaches 59 mm in height and 25 mm in diameter. It is imperforate, elongated ovate, solid, smooth, and glossy, and colored sulfur-yellow. The shell has seven moderately convex whorls, which are slightly constricted near the suture. The body whorl makes up nearly two-thirds of the total shell length. The aperture is ovate-lunate, somewhat angular, and slightly effuse at the base. The lips are white, broadly revolute, and not flattened. The columella is white; the callus that connects the two ends of the peristome is pitch-black, as far as it is visible inside the shell. A line of this same black color, which marks a former growth stage, stretches from the center of the callus across the penultimate whorl.
Amphidromus atricallosus and its subspecies are distributed across Southern Myanmar; southern and eastern Thailand, including Thailand's Sakaeo Province; it is also widely distributed throughout Peninsular Malaysia, and is found in Singapore.
