Acarospora pseudofuscata is a species of saxicolous (rock-dwelling) crustose lichen in the family Acarosporaceae.

The type specimen was collected west of the village of Emborios on the island of Kalymnos, at an altitude of about 50 m (160 ft).

[1] Acarospora pseudofuscata has a dark brown, crustose thallus forming patches that are often over 10 cm (3.9 in) wide.

They start out rounded, with a diameter of 0.1–0.2 mm, eventually growing to mostly fill the areole with a dark brown, slightly depressed, smooth disc.

[1] Acarospora pseudofuscata occurs on Santorini, Paros, Kalymnos, and Kos, all island groups in the Aegean Sea.