Micrarionta opuntia

Micrarionta opuntia, known as the prickly pear island snail, pricklypear islandsnail, or prickly pear snail, is a species of land snail in the  family Xanthonychidae. It is endemic to California, first formally described in 1975.

The type locality is northeastern San Nicolas Island, at the base of a prickly pear (Opuntia littoralis), in a small depression. It reaches around 10.5 mm in diameter.