LichenIreland
  • Pertusaria flavida (DC.) J.R.Laundon
Pertusaria flavida
Click on map to open large map in new window
(Map updated: 11 August 2009)

Click here to view an interactive map of the Northern Ireland dataset as currently collated by CEDaR.
The map is generated through the NBN Gateway using their Interactive Mapping Tool.

 

This crustose epiphyte occurs mostly without discs (that is, in the sterile state), so is easily confused with other species which have a yellowish thallus and a C+ orange, spot test reaction. Since it grows equally well on the rough or smooth bark of well-illuminated deciduous trees in undisturbed woodland, parkland or along waysides, the key to its identification lies in the thallus which is yellow-green with abundant rounded isidia which soon dissolve into soredia. In fact they can often obscure the thallus completely. It has a more intense, green-yellow appearance than any of its look-a-likes and is UV+ orange (a standard UV source will confirm this). In the herbarium of museums it can retain its fresh colour for years. Lecanora expallens is thinner, duller and UV-; Pyrrhospora quernea has a brown tinge and is very finely granular; Ochrolechia inversa is UV+ pink, has fine-powdery soralia, is paler, almost beige in colour. Thinly scattered; absent from south-east Ireland.

Key characteristics

  • Almost luminous yellow-green thallus with rounded isidia which dissolve into soredia
  • UV+ orange.

Original text submitted by Vince J. Giavarini

 Simms, M. J., (2016). Pertusaria flavida (DC.) J.R.Laundon. [In] LichenIreland.
http://www.habitas.org.uk/lichenireland/species.asp?item=19393 Accessed on 2017-11-22.