Chlorostoma rugosum A. Adams, 1851 (original combination) Tegula rugosa, common name the rough top shell, is a species of sea snail, a marine gastropod mollusk in the family Tegulidae.

The solid, heavy shell is narrowly umbilicate and has a conoidal shape.

It is dull cinereous, more or less variegated by brown, blackish or red streaks.

The about 5 whorls are obliquely striate, radiately coarsely and irregularly plicate and rugose above, sometimes nearly smooth.

The edge of the columella is rather deeply curved above the tooth, but spreading at its junction with the whorl, bounding and somewhat narrowing the umbilicus by a white callus, which does not extend to the upper margin of the aperture.