''Punctelia nebulata'' is a species of

foliose lichen Foliose lichen is one of the morphological classes of lichens, which are complex organisms that arise from the symbiotic relationship between fungi and a photosynthetic partner, typically algae. This partnership allows lichen to live in diverse ...

in the family

Parmeliaceae The Parmeliaceae is a large and diverse family of Lecanoromycetes. With over 2700 species in 71 genera, it is the largest family of lichen-forming fungi. The most speciose genera in the family are the well-known groups: '' Xanthoparmelia'' ( 822 ...

. Found in Australia, it was formally described as a new species in 1988 by lichenologists John A. Elix and Jen Johnston. The type was collected in

New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ...

, on a roadside north of

Gilgandra Gilgandra is a country town in the Orana region of New South Wales, Australia, and services the surrounding agricultural area where wheat is grown extensively together with other cereal crops, and sheep and beef cattle are raised. Sitting at t ...

. The lichen grows on ''

Callitris ''Callitris'' is a genus of coniferous trees in the Cupressaceae (cypress family). There are 16 recognized species in the genus, of which 13 are native to Australia and the other three (''C. neocaledonica, C. sulcata'' and ''C. p ...

'' trees in semi-

arid A region is arid when it severely lacks available water, to the extent of hindering or preventing the growth and development of plant and animal life. Regions with arid climates tend to lack vegetation and are called xeric or desertic. Most ar ...

, inland regions of southern Australia. It has a foliose

thallus Thallus (plural: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. Many of these organisms wer ...

closely attached to its substrate. The upper surface of the thallus is pale grey to mineral grey, sometimes blackening with age. The thallus is up to in diameter, made of somewhat irregularly shaped, crowded lobes measuring wide. The lower surface of the thallus is pale. The major

secondary compounds Secondary metabolites, also called specialised metabolites, toxins, secondary products, or natural products, are organic compounds produced by any lifeform, e.g. bacteria, fungi, animals, or plants, which are not directly involved in the norma ...

in ''Punctelia nebulata'' are

atranorin Atranorin is a chemical substance produced by some species of lichen. It is a secondary metabolite belonging to a group of compounds known as depsides. Atranorin has analgesic, anti-inflammatory, antibacterial, antifungal, cytotoxic, antioxidant, ...

and chloroatranorin. ''Punctelia nebulata'' had been previously misidentified with ''

Punctelia subalbicans ''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. Taxonomy The lichen was first described as a new species by Jame ...

'', from which it can be only reliably identified using chemical methods: ''P. subalbicans'' contains

lecanoric acid Lecanoric acid is a chemical produced by several species of lichen.ubChem - Lecanoric acid"> Lecanoric acid is classified as a polyphenol and a didepside and it functions as an antioxidant. The acid is named after the lichen ''Lecanora''. The acid ...

in the

medulla Medulla or Medullary may refer to: Science * Medulla oblongata, a part of the brain stem * Renal medulla, a part of the kidney * Adrenal medulla, a part of the adrenal gland * Medulla of ovary, a stroma in the center of the ovary * Medulla of th ...

, whereas the thallus of ''P. nebulata'' does not have any lichen acids.

References

nebulata Lichen species Lichens of Australia Lichens described in 1988 Taxa named by John Alan Elix {{Parmeliaceae-stub