Pyrenula luteopruinosa is a species of corticolous (bark-dwelling), crustose lichen in the family Pyrenulaceae.

The type specimen was collected near a frog trail (genus Dendrobates) in Bahía Honda, Veraguas; in this habitat in lowland rainforest on the Pacific coast of Panama, the lichen was found growing on the smooth bark of a tree.

Its apothecia are in the form of perithecia, partially immersed in the substrata, measuring 0.5–0.6 mm in diameter.

The perithecia are covered by a characteristic lemon-yellow pruina – dust-like particles of crystalline pigment.

The ascospores are ellipsoid to somewhat cylindrical with conical ends, have 3 septa, and typically measure 14–19 by 8–10 μm.