Conus antoniaensis is a species of sea snail, a marine gastropod mollusc in the family Conidae, the cone snails, cone shells or cones.

[1][self-published source] These snails are predatory and venomous.

The shell is conical with a sharply-angled shoulder.

The spire whorls are flattened and lack grooves.

This species occurs in the Atlantic Ocean off Boa Vista Island, Cape Verde.