[1] It is monotypic,[2] containing the single species Lithoglypha aggregata, a saxicolous (rock-dwelling), crustose lichen found in South Africa.

The genus name is derived from the Greek roots lithos ("rock") and glyphe (referring to writing or engraving on a stone tablet).

[3] The genus Lithoglypha is characterised by a thallus that is endolithic, meaning it grows within the interior of rocks, presenting a crustose (crust-like) appearance.

[3] The apothecia (fruiting bodies) of Lithoglypha initially develop in a cleistotheciform (closed) manner, later transforming into a pseudolecideine form, which indicates a transition in their developmental stages.

[3] The hymenium itself is hyaline (translucent) and varies in height from 50 to 100 μm, displaying a reaction that turns from blue to wine-red upon the addition of iodine, a diagnostic feature in identifying lichen species.