Myeloconis guyanensis is a species of corticolous (bark-dwelling), crustose lichen in the family Porinaceae. Found in the coastal lowlands of eastern Guyana, it was formally described as a new species in 1996 by Patrick M. McCarthy and John Elix. Characteristics of the lichen include the prominent on the , its yellow, medulla, and the variety of lichen products found in the medulla.