Verrucaria serpuloides is a species of saxicolous (rock-dwelling), crustose lichen belonging to the family Verrucariaceae. It is native to the Antarctic Peninsula. It is one of only two permanently submerged species of lichen, the other being , and the only one found permanently submerged in a marine environment. Collections of the species were first made in 1944 by Elke Mackenzie. The species has been discovered living up to 10 m (33 ft) below mean high tide. It creates jet-black patches on the base of submerged rocks. It uses green algae as a symbiont.