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Punctelia
''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 (asexual spores), simple rhizines (root-like structures that attach the lichen thallus to its substrate), and point-like pseudocyphellae (tiny pores on the thallus surface that facilitate gas exchange). It is this last feature that is alluded to in the vernacular names speckled shield lichens or speckleback lichens. ''Punctelia'' lichens grow on bark, wood, and rocks. The genus has a worldwide distribution, occurring on all continents but Antarctica. Species are found in temperate to subtropical locations. ''Punctelia'' has centres of distribution in the Neotropics and Africa; about half of the known species occur in South America. The photobiont partners of ''Punctelia'' are green algae in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Punctelia Borreri
''Punctelia borreri'' is a species of foliose lichen in the family Parmeliaceae. It is a common and widely distributed species, occurring in tropics, tropical, subtropics, subtropical, and temperate climate, temperate regions of Africa, Asia, Europe, North America, Oceania, and South America. The lichen typically corticolous lichen, grows on bark of deciduous trees, and less commonly saxicolous lichen, on rock. Some European countries have reported increases in the species distribution, geographic range or regional frequency of the lichen in recent decades, attributed alternatively to a reduction of atmospheric sulfur dioxide, sulphur dioxide levels or an increase in temperatures resulting from climate change. The lichen is characterised by a greenish-grey to bluish-grey upper thallus surface, a black lower surface, pseudocyphellae on the surface of the thallus (tiny pores that facilitate gas exchange), and chemically, by the presence of gyrophoric acid in the medulla (licheno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
