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

It does not have a shield-shaped involucrellum, which is typical of several other species in genus Bagliettoa.

The excipulum (the rim of tissue around the ascomata) measures 0.2–0.3 mm in diameter and lacks colour other than the upper part, which is purple.

It has also been recorded from North America, although it is not certain if this represents a distinct species.

[3] It had been shuffled to several genera in its taxonomic history, before being transferred to Bagliettoa in 2007.