Flavoparmelia caperata, the common greenshield lichen, is a medium to large foliose lichen that has a very distinctive pale yellow green upper cortex when dry. The rounded lobes, measuring {{convert|3|–|8|mm|in|1|abbr=on}} wide, usually have patches of granular soredia arising from pustules. The lobes of the thallus may be smooth, but quite often have a wrinkled appearance especially in older specimens. The lower surface is black except for a brown margin; rhizoids attached to the lower surface are black and unbranched.

Habitat

On bark of trees, but occasionally on rock.

Similar species

The very similar Flavoparmelia baltimorensis grows mainly on rock and has globose, pustular outgrowths (somewhat similar to isidia) on the upper surface of the lobes, but does not produce granular soredia.

Lichen checklists containing Flavoparmelia caperata

• A cumulative checklist for the lichen-forming, lichenicolous and allied fungi of the continental United States and Canada. North Dakota State University.  
• British Lichens - List of Lichens & Lichenicolous Fungi. [https://web.archive.org/web/20070629165928/http://www.thebls.org.uk/content/listeh.html]
• Checklist to Norwegian lichens: Accepted names. [https://web.archive.org/web/20070518232452/http://www.toyen.uio.no/botanisk/bot-mus/lav/bmlnosj.htm]
• Checklist of Japanese Lichens. [https://web.archive.org/web/20060513055135/http://home.hiroshima-u.ac.jp/lichen/cklist.htm#F]
• Checklist of the Lichens of Australia and its Island Territories (see Flavoparmelia haysomii).  

Images of Flavoparmelia caperata on the internet

• Wayne Armstrong's Foliose Lichens.  
• Flechtenbilder, Ulrich Kirschbaum.  
• The Lichen Herbarium, University of Oslo, Norway.  
• Stephen Sharnoff's Lichen Images.  
• Index-Lichens, Leif & Anita Stridvall.  

References