Resembling a small abalone by the shape of its shell, or a keyhole limpet with its oversized body, this animal is neither, instead being a top shell related to the periwinkles (Family Trochidae). This fast moving animal can be found under rocks. Its shell pattern is variable, usually a mix of blacks, greys and whites, with a similar monochromatic but patchy body, covered in small pustules. The shell is sculptured with spiral grooves, which may be almost microscopic, and can also be iridescent, even on the upper surface. In spite of the previously mentioned similarities, and resemblance to other snail species is superficial, and this species does not closely resemble any other on closer inspection.
