Verrucaria simplex is a species of saxicolous (rock-dwelling), crustose lichen in the family Verrucariaceae.

The type specimen was collected by Brian Coppins from Morpeth, Northumberland; there, it was found growing on a fragment of mortar-cement lying on the floor of a woodland.

[3] The dark brown, crust-like thallus of Verrucaria simplex is epilithic, meaning it grows on the surface of its substrate.

When the lichen is wet, it becomes greenish, pulp-like and translucent,[1] described as resembling "film-like crusts of green algae".

[2] The photobiont partner of the lichen is a green alga with more or less spherical cells that measure 4–8 μm in diameter.