[5] Molecular phylogenetics studies demonstrated that P. solorinoides was not closely related to true Calenia species, but instead showed closer affinities to the morphologically distinct genera Roselviria and Santricharia.

The fungal body (thallus) appears scattered or dispersed rather than forming a continuous coating, with distinctive swollen, bubble-like patches that rise up from the leaf surface.

[4] The species produces specialised reproductive structures called hyphophores, which are short, bristle-like projections that emerge from the margins of the thallus patches.

[4] A unique feature of P. solorinoides is that it produces just a single ascospore per reproductive sac (ascus), rather than the multiple spores typical of many lichens.

These spores are muriform, meaning they are divided by both vertical and horizontal walls into multiple compartments, creating a brick wall-like appearance when viewed under magnification.