Punctelia subalbicans is a species of foliose lichen in the family Parmeliaceae. It is found in Australia and New Zealand, where it grows on the bark of various tree species.
The taxon Punctelia pallescens, described by Syo Kurokawa in 1999 as a new species from western Australia,[5] was later determined to be identical chemically and morphologically with P. subalbicans,[6] and it is now considered a synonym.[7]
Description
The pale greenish-grey thallus of Punctelia subalbicans typically measures 5–10 cm (2–4 in) in diameter. Lobes comprising the thallus are irregularly shaped with rounded tips and are scalloped with dark margins; they are usually 2–5 mm (0.08–0.20 in) wide. Pseudocyphellae occurs along the margins of the lobes, and on the exciples (the ring-shaped layers surrounding the hymenium that develop into distinct margins) of the apothecia. The thallus undersurface is pale buff or cream, with a sparse to moderate number of rhizines, which themselves are unbranched and more or less the same colour as the thallus undersurface. The thallus surface lacks vegetative propagules such as isidia or soralia. Apothecia are common, especially near the centre of the thallus, and are up to 6 mm (0.24 in) across with a concave to flattened central disc that is brownish-red to dark brown in colour. Ascospores are 9–14 by 8–10 μm. The major secondary chemicals found in this species are lecanoric acid, atranorin, and chloroatranorin.[4] The lecanoric acid derivative 5-chlorolecanoric has also been detected in this species.[6]
^Galloway, D.J. (1983). "New taxa in the New Zealand lichen flora". New Zealand Journal of Botany. 21 (2): 191–200. doi:10.1080/0028825X.1983.10428544.
^Kurokawa, S. (1999). "Notes on Flavopunctelia and Punctelia (Parmeliaceae), with descriptions of four new species". Bulletin of the Botanical Garden of Toyama. 4: 25–32.