Punctelia is a genus of foliose lichens belonging to the large family Parmeliaceae. The genus, which contains about 50 species, was segregated from genus Parmelia in 1982. Characteristics that define Punctelia include the presence of hook-like to thread-like conidia, simple rhizines, and point-like pseudocyphellae. It is this last feature that is alluded to in the vernacular names speckled shield lichens or speckleback lichens.
Crespoa is a genus of five species of lichen in the family Parmeliaceae. Species in this genus are characterized by having an upper thallus surface that is wrinkled and reticulately ridged to coarsely foveolate.
Punctelia rudecta, commonly known as the rough speckled shield or the speckleback lichen, is a North American species of foliose lichen in the family Parmeliaceae. This species can be readily identified by the light color of the thallus underside, the relatively large lobes at the edges of the thallus, and the tiny white pores present on the top of the thallus that are characteristic of the genus Punctelia. The lichen is quite abundant and widespread in the eastern and southeastern United States, although it also occurs in Canada and northern Mexico, but is less common in these regions. The lichen usually grows on bark, and less commonly on shaded rocks. There are several lookalike Punctelia species; these can often be distinguished from P. rudecta by differences in distribution or in the nature of the reproductive structures present on the thallus.
Punctelia transtasmanica is a species of foliose lichen in the family Parmeliaceae. It is found in Australasia.
Punctelia purpurascens is a species of foliose lichen in the family Parmeliaceae. Found in Brazil, it was formally described as a new species in 2007 by lichenologists Marcelo Marcelli and Luciana da Silva Canêz. The type specimen was collected in the municipality of Vicara in the southern Brazilian state of Rio Grande do Sul. There it was found growing on a basaltic rock in an open field. The specific epithet purpurascens refers to the unusual K+ purple reaction of the medulla.
Punctelia eganii is a species of foliose lichen in the family Parmeliaceae. It was described as a new species in 2011 by Brendan Hodkinson and James Lendemer. It is named in honor of Robert S. Egan, U.S. lichenologist and professor of biology, who collected the type specimen. The lichen is morphologically identical to Punctelia rudecta, differing only in the production of the secondary metabolite lichexanthone, which was previously unknown in the genus Punctelia. The presence of this compound allows the two species to be distinguished with the use of ultraviolet light, which causes the pseudocyphellae of P. eganii to fluoresce. The type specimen was found in a beech-Magnolia forest in Haines Island Park in Monroe County, Alabama.
Punctelia nashii is a species of foliose lichen in the family Parmeliaceae. It is known only from California.
Punctelia constantimontium is a species of foliose lichen in the family Parmeliaceae. Its range includes South America, Africa, and Mexico, where it grows on bark and twigs.
Punctelia appalachensis, commonly known as the Appalachian speckled shield lichen, is a species of foliose lichen in the family Parmeliaceae. It is found in the eastern United States and eastern Canada. The lichen was first formally described in 1962 by lichenologist William Culberson as a species of Parmelia. He collected the type specimen growing on tree bark in West Virginia, Hildur Krog transferred it to the newly circumscribed genus Punctelia in 1982.
Punctelia reddenda is a widely distributed species of foliose lichen in the family Parmeliaceae. It occurs in Africa, Europe, North America, and South America, where it grows on bark and on rock.
Punctelia subpraesignis is a species of foliose lichen in the family Parmeliaceae. It occurs in Mexico, South America, and East Africa, where it grows on bark and on rocks. Major characteristics of the lichen that distinguish it from other Punctelia species include the C+ and KC+ rose spot tests of the medulla, ascospores that are smaller than 20 μm, and unciform (hooklike) conidia.
Punctelia cedrosensis is a species of foliose lichen in the family Parmeliaceae. It is endemic to Mexico, where it grows on the bark of conifers.
Punctelia punctilla is a species of foliose lichen in the family Parmeliaceae. It is found in Africa, South America, and North America, where it grows on bark and on rocks. The main characteristics that distinguish Punctelia punctilla from other species of Punctelia are the presence of isidia on the thallus surface, a pale brown thallus undersurface, and the presence of lecanoric acid in the medulla.
Punctelia bolliana, the eastern speckled shield lichen, is a species of foliose lichen in the family Parmeliaceae. 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. It grows on the bark of both deciduous trees and coniferous trees. 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.
Punctelia perreticulata is a widely distributed species of foliose lichen in the family Parmeliaceae. It occurs in Mediterranean Europe and Russia, North America, South America, Australia, and New Zealand, where it grows on rocks, bark, or wood. Its main distinguishing features are its thallus surface, marked with many shallow depressions, grooves, or pits, and sorediate pseudocyphellae. The lower side of the thallus is ivory to tan towards the centre and the major secondary metabolite in the medulla is lecanoric acid. A lookalike species with which it has been historically confused is Punctelia subrudecta; this lichen can be distinguished from Punctelia perreticulata by the texture of the thallus surface, or, more reliably, by the length of its conidia.
Punctelia graminicola is a species of foliose (leafy) lichen in the family Parmeliaceae. It grows on rocks, and, less frequently, on bark in North America, South America, and East Africa. It has a blue-grey thallus measuring up to about 15 cm (6 in), covered with tiny pores called pseudocyphellae. Sometimes the lichen forms small lobes that project out from the surface. Fruiting bodies are uncommon in this species; if present, they resemble small cups with a brown internal disc measuring 3–10 mm (0.1–0.4 in) in diameter. A lookalike species, Punctelia hypoleucites, is not readily distinguishable from Punctelia graminicola by appearance or habitat alone; these species can only be reliably differentiated by examining the length of their conidia.
Cetrelia chicitae is a species of foliose lichen in the family Parmeliaceae. It is found in eastern Asia, North America, and Europe, where it grows on mossy rocks and tree trunks.
Punctelia borreri is a species of foliose lichen in the family Parmeliaceae. It is a common and widely distributed species, occurring in tropical, subtropical, and temperate regions of Africa, Asia, Europe, North America, Oceania, and South America. The lichen typically grows on bark of deciduous trees, and less commonly on rock. Some European countries have reported increases in the geographic range or regional frequency of the lichen in recent decades, attributed alternatively to a reduction of atmospheric sulphur dioxide levels or an increase in temperatures resulting from climate change.
Hypogymnia flavida is a species of foliose lichen in the family Parmeliaceae. It is found in mountainous locations of east Asia, where it grows on the bark and wood of woody plants. It has a relatively large yellowish thallus.
Parmelia fraudans is a species of foliose lichen in the family Parmeliaceae. It is found in Europe and North America, where it grows on rocks.
