Amastra thaamuni
Amastra thaamuni is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusc in the family Amastridae.
Description
The length of the shell attains 14.98 mm, its diameter 9.5 mm.The shell contains 6 whorls. The shell is sinistral, imperforate, and moderately solid, with an oblong shape and a somewhat silky luster. The spire is broadly conic with slightly convex outlines and a relatively obtuse summit.
The whorls of the protoconch are marked only by faint, very fine growth striae, while the later whorls exhibit distinct, oblique striation with fine, thread-like ridges. The upper whorls are purplish-brown with irregular whitish streaks, and the last two whorls are covered by a rich, dark chestnut cuticle. This cuticle is yellowish near the suture and becomes deciduous in front of the aperture, revealing a glossy, light green underlayer beneath.
The aperture is moderately oblique, with a livid or bluish-white interior. A whitish callous rim lines the interior of the dark-edged lip. The columella is short and bears a strong, triangular lamella that bends downward. The parietal callus is thin.