Punctelia nashii
Punctelia nashii is a species of foliose lichen in the family Parmeliaceae. It is known only from California.
Taxonomy
The lichen was described as a new species in 2011 by the Brazilian lichenologists Marcelo Marcelli and Luciana da Silva Canêz. The type specimen was collected from the Hastings Natural History Reservation in Monterey County, a biological field station of the University of California. Here it was found growing on blue oak at an elevation of. The specific epithet nashii honors Thomas Hawkes Nash III, "in recognition of his support and for collecting the holotype".Description
The lichen has a greenish-colored thallus about, comprising irregularly branched lobes measuring wide. Soralia on the thallus surface are whitish, with granula soredia. This species does not produce isidia. The pseudocyphellae are few, and described as "inconspicuous". The undersurface of the thallus ranges from white to yellowish-brown. There are rhizines, both twisted short ones, and longer, sparser ones; both are brown, and always darker than the undersurface. Apothecia are absent.The main secondary compounds in Punctelia nashii are atranorin and lecanoric acid. The lichen spot tests that give positive reactions in the upper cortex are K+, and in the medulla C+, and KC+.