Parmeliopsis ambigua

Common name	Green Starburst	Code: PARMAMB
Field Characters	Small, leafy chlorolichens. Thalli often circular, 5-10 cm across. Narrow, tightly appressed lobes typically 0.5-2 mm wide. Upper cortex pale yellow with laminal, circular soralia common throughout. Lower surface brown with sparse, short, simple rhizines. Farinose soredia present in laminal soralia. Apothecia are rare; when present they have a brown disc and often a sorediate margin.
Similar species & genera	Parmeliopsis hyperopta; grey, upper cortex K+ yellow, KC-. Arctoparmelia incurva, A. subcentrifuga: on rock, cortices typically dull, lower cortex pale or mousy-grey to purplish-black. For some collections thin layer chromatography may be required. Arctoparmelia contains alectoronic acid in the medulla while P. ambigua contains divaricatic acid – both react UV+ blue-white.
Ecology	Commonly epiphytic or on downed wood (often lignum), abundant across Alberta’s forested regions. Rare in the parklands, absent from the grasslands. Common niches include the base of coniferous trees or on deciduous shrubs. In the shield and mountain regions, it can also be found on rock, where it may be mistaken for Arctoparmelia.
Chemistry	Upper cortex KC+ yellow, K- or K+ pale yellow, PD-, C-, UV- (usnic acid). Medulla KC-, K-, PD-, C-, UV+ blue-white (divaricatic acid).
Molecular support
Links	ABMI Biodiversity Browser Consortium of Lichen Herbaria Ways of Enlichenment Photo Gallery
Gallery