Lecanora louisianae is a species of corticolous (bark-dwelling), crustose lichen in the family Lecanoraceae.

It was formally described as a new species in 1932 by French lichenologist Maurice Bouly de Lesdain.

[1] It is common and widespread in the Coastal Plain region of southeastern North America.

[2] Arthonia agelastica is a lichenicolous fungus that parasitises Lecanora louisianae.

Some other lichenicolous fungi recorded on L. louisianae include Skyttea lecanorae, Chaenothecopsis kalbii, and Taeniolella delicata.