Porpidia submelinodes is a species of saxicolous (rock-dwelling), crustose lichen in the family Lecideaceae.

[1] Found in the South Shetland Islands of Antarctica, it was formally described as a new species in 2011 by lichenologists Piotr Osyczka and Maria Olech.

The type specimen was collected from Penguin Island, where it was found growing on a volcanic boulder.

The lichen has a rusty orange thallus comprising distinct rounded areoles surrounded by deep cracks, and an inconspicuous black prothallus.

All chemical spot tests are negative, and the species does not contain any lichen products detectable with thin-layer chromatography.