Originally, the genus contained 22 species segregated from Parmelia based on differences in the development of the pseudocyphellae, secondary chemistry, and phytogeography.

[1] Mason Hale later identified Flavopunctelia as a separate genus with four species, based on conidial shape and chemical traits.

[10] In 2017, Pradeep Divakar and colleagues applied a "temporal phylogenetic" approach to define taxonomic ranks within Parmeliaceae, inferring that groups of species diverging 29.45–32.55 million years ago signify distinct genera.

Although the authors (Arne Thell, Ingvar Kärnefelt, and Mark Seaward) recognized Nesolechia's place in Parmeliaceae and its morphological reduction in Punctelia, they suggest that "since the parasitic genera appear as sister groups ... synonymization feels hardly necessary".

[12] Robert Lücking, critiquing the temporal phylogenetic method, also dismissed the proposed synonymy, stating that merging genera based solely on divergence time does not align with taxonomy's need to mirror evolutionary history.

[9] Punctelia lichens are medium-sized, foliose (leafy), and grey to greyish-green,[7] although collected specimens gradually lose their colour tone.

In comparison, Punctelia pseudocyphellae are rounded (orbicular) and laminal, although in some species the cortex gets pushed around the edges of the thallus, giving them a marginal appearance.

[1] Pseudocyphellae are termed conspicuous when they can be viewed with the naked eye, inconspicuous when a hand lens or microscope is needed to see them, and subtle for intermediate states where they can be seen only with concerted effort.

[19] An investigation centred on the lichen species Punctelia borreri and P. subrudecta, which are prominent in Europe's temperate and Mediterranean forest ecosystems, confirmed that these fungi predominantly collaborate with Trebouxia gelatinosa.

[7] However, P. constantimontium and P. subpraesignis have been recorded utilising cement mortar as a growing surface in Verónica, Buenos Aires.

[22] Revised accounts of the genus have been published for several European countries in recent decades, including Norway (2000),[26] Switzerland (2003),[27] Denmark (2007),[28] Lithuania (2010),[29] and Poland.

Because it has an abundant and widespread population in North America with no sign of decline, Punctelia caseana is considered a species of least concern.

These include: Abrothallus parmeliarum, Didymocyrtis melanelixiae, Epithamnolia xanthoriae, Lichenoconium usneae, Llimoniella bergeriana, Lichenohendersonia uniseptata, Nesolechia oxyspora, Pronectria oligospora, Pyrenidium sp., Rinodina conradii, Sphaerellothecium reticulatum, Tremella parmeliarum, Trichosphaerella buckii, and Xenonectriella subimperspicua.

One research study identified apparent signs of damage on thalli in areas potentially affected by air pollution.

The researchers suggested that the distinctive colour changes seen on Punctelia thalli could result from pollutants affecting the thylakoid membranes of the trebouxioid algae.

[20] A study conducted in Spain observed Punctelia borreri and P. subrudecta reappearing in areas with a decline in SO2 pollution.

[60] Two Punctelia species have been recommended for use as element bioindicators in air pollution monitoring studies in the eastern United States.

Punctelia rudecta is suggested for use in cooler forested uplands, and P. missouriensis for use in isolated woodlands or urban areas.

[61] Because of the widespread occurrence of P. hypoleucites in both urban and industrial sites in and around Tandil, Argentina, it has been proposed as a potential biomonitor of air pollution in that city.

[62] Punctelia borreri has been used in traditional Chinese medicine as an alleged remedy for a variety of ailments, including chronic dermatitis, blurred vision, bleeding from the uterus or from external injuries, and for sores and swelling.