Genoplesium cornutum, known as Corunastylis cornuta in Australia, is a small terrestrial orchid endemic to the Australian Capital Territory and nearby parts of New South Wales. It was first formally described in 2008 by David Jones who gave it the name Corunastylis cornuta from a specimen collected from the Black Mountain Reserve and the description was published in The Orchadian. In 2014 Julian Shaw changed the name to Genoplesium cornutum. The specific epithet (cornutum) is a Latin word meaning bearing horns.