''Pseudephebe minuscula'' is a species of

fruticose lichen A fruticose lichen is a form of lichen fungi that is characterized by a coral-like shrubby or bushy growth structure. It is formed from a symbiotic relationship of a photobiont such as green algae or less commonly cyanobacteria and one, two or mor ...

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 ...

. In North America, it is known

colloquially Colloquialism (), also called colloquial language, everyday language or general parlance, is the style (sociolinguistics), linguistic style used for casual (informal) communication. It is the most common functional style of speech, the idiom norm ...

as coarse rockwool. It has an antitropical distribution.

Description

The lichen has a dark brown to almost black filamentous

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 ...

, comprising individual cylindrical branches, closely attached to the rock substrate, often flattened, measuring 0.2–0.5 mm thick. It is common in windswept arctic and alpine environments, where it grows on

granitic A granitoid is a generic term for a diverse category of coarse-grained igneous rocks that consist predominantly of quartz, plagioclase, and alkali feldspar. Granitoids range from plagioclase-rich tonalites to alkali-rich syenites and from quart ...

rocks and pebbles.

References

Parmeliaceae Lichens of Antarctica Lichens of Asia Lichens of Europe Lichens of Subarctic America Lichens described in 1878 Lichen species Taxa named by William Nylander (botanist) Taxa named by Ferdinand Christian Gustav Arnold Lichens of the Arctic {{Parmeliaceae-stub