A foliose species with a smooth, slightly shiny thallus that is dark brown to almost black, ascending and much contorted so as to appear multi-lobed. This contortion means the black under surface is often visible.
Medulla: C+ red, K-
Umbilicaria polyphylla is mainly found in upland Scotland, where it grows on hard, siliceous but nutrient-enriched rocks. BLS distribution map
scottishlichens.co.uk 