The type specimen was collected from Apiaí (São Paulo, Brazil), by botanist Juan Ignacio Puiggari.

The original description noted its similarity to Punctelia rudecta, with differences in the grey colour of the thallus, the pale apothecia, and the much larger spores.

This complex of morphologically similar species includes P. borrerina, P. riograndensis, P. jujensis, and P. subpraesignis; all occur in South America.

[4] In an assessment of the potential use of local lichens as air quality biomonitors in central Argentina, Punctelia microsticta was determined to be a pollution-tolerant species.

Although the lichen typically occurs on the bark of trees and shrubs,[5] one report from Argentina noted its growth on the painted metal bars of the "La Postrera", an iron bridge on Provincial Route 2.