| Rhizoplaca chrysoleuca | |
|---|---|
 | |
Scientific classification  | |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Lecanoromycetes |
| Order: | Lecanorales |
| Family: | Lecanoraceae |
| Genus: | Rhizoplaca |
| Species: | R. chrysoleuca |
| Binomial name | |
| Rhizoplaca chrysoleuca | |
| Synonyms | |
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Rhizoplaca chrysoleuca (orange rim lichen, [2] rock-posy lichen, rockbright) is a pale yellowish-green to gray-green umbilicate foiliose lichen in the Lecanoraceae (rim lichen) family. [3] [4] It was first described in 1791 by English botanist Sir James Edward Smith as Lichen chrysoleucus; Friedrich Wilhelm Zopf transferred it to the genus Rhizoplaca in 1905.
The single-leaf (monophyllous) umbilicate thallus can be 2–3.5 cm in width, with deep lobes. [4] The thallus is relatively thick and lumpy with warts and lobules. [3] The fruiting structures (apothecia have lightly pruinose, burnt-orange to tan discs rimmed, with a contrasting rim of pale greenish thallus-like tissue making them easy to identify. [3] Apothecia are 0.8–2.5 mm diameter, and often numerous and crowded into each other. [4]
It grows in Eurasia and western North America. In the Sonoran Desert region it grows at elevations from 1,200 to 3,200 metres (3,900 to 10,500 ft). [4] It prefers siliceous rock, granite, schist, quartz, mica, and basalt, but is also found on sandstone and less commonly on calcareous rock. [4] It grows from the high desert to the alpine zone. [4] It is often nitrophilous, [4] preferring dropping areas under bird perches.[ citation needed ] It is common on rock in inland arid mountain and desert habitats in California. [3] : 118
Lichen spot tests are K+ yellow or K−, KC+ yellow-orange, C−, and P− on the cortex, and K−, KC+ red or KC−, C−, and P+ yellow or P− on the medulla. [3]