Buellia phillipensis is a little-known species of saxicolous (rock-dwelling), crustose lichen in the family Caliciaceae,[1] described in 2020.

[2] The thallus of Buellia phillipensis is crustose and has a rimose to rimose-areolate texture, spreading up to 15 mm wide.

The apothecia are small, 0.1–0.4 mm wide, initially lecanorine then changing to biatorine or lecideine, and separate or grouped.

The proper exciple is thin, persistent, and black, with an outer zone that is aeruginose-black, 25–30 μm thick.

Known only from its type locality, Buellia phillipensis was collected from a rock outcrop in a valley dominated by African olive trees.