Punctelia bolliana

It is found in North America, with a distribution extending from the Canadian province of Ontario south to the central and northeastern United States and Mexico.

The combination of characteristics that distinguishes this species from others in genus Punctelia are the absence of the vegetative propagules isidia and soralia, a pale brown lower thallus surface, and the presence of the secondary chemical protolichesterinic acid in the medulla.

[1] In 1982 Norwegian botanist Hildur Krog transferred it to Punctelia, a genus she circumscribed to contain Parmelia species with point-like (punctate) pseudocyphellae.

[3] Isidia and soralia are absent; the lobules are thought to function as a vegetative propagule, although they are noted to be "robust and not easily fragmenting".

[4] The set of characteristics that define Punctelia bolliana and differentiate it from other members of the genus are: the absence of soralia and isidia; a brown lower thallus surface; fatty acids in the medulla (C−); hook-like (unciform) conidia; and ascospores that measure less than 20 μm.

[5] Molecular phylogenetic analysis shows that it is closely related to Punctelia appalachensis, a North American species that also has fatty acids as the main medullary component.