These include a dark, velvety lower thallus surface that usually lacks rhizines, a negative test for lichenan, and a high concentration of usnic acid and atranorin in the cortex.

He also considered placement in Arctoparmelia due to similarities in lobe configuration, cortical chemistry, and the presence of a velvety lower surface.

However, other differing characteristics precluded this classification, including a complete lack of rhizines and the presence of isolichenan in the cell walls.

[4] In 2006, molecular data supported the transfer of Xanthoparmelia peruviensis to Psiloparmelia, despite it not sharing all the morphological features characteristic of other species in the genus, particularly in having a densely rhizinate lower surface.

The apothecia are either attached directly to the thallus surface (adnate), or are mounted on a small stalk (substipitate); they measure 2–5 mm in diameter.

Twelve of the thirteen species in the genus are found in high altitudes on the Andes Mountains, ranging from Ecuador and Peru south to Bolivia and northern Argentina.

Psiloparmelia arhizinosa is the only species to break this distributional pattern; it is found at alpine habitats at high elevations 3,000–3,300 ft (910–1,010 m) in Lesotho.