[3] Found in the Orenburg region of Russia, this species prefers to grow on lime-rich schist and sandstone boulders and pebbles in scrubs and steppes.

The lichen was first formally described as a new species in 2016 by the lichenologists Ivan Frolov, Karina Wilk, and Jan Vondrák, who initially classified it in the genus Caloplaca.

The type specimen was collected in Russia, specifically in the Orenburg region, within the Sakmara district near the village of Grebeni.

[4] The thallus of Pyrenodesmia micromontana is epilithic (growing on the rock surface), typically less than 150 μm thick, and shows no distinct cortex.

It grows on limestone, lime-rich schist, and sandstone, often accompanied by lichen species such as Acarospora moenium, Polyozosia dispersa, and Sarcogyne regularis.