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crust lichen, on granitic rock
THALLUS: medium tan to grayish-tan, convex-areolate, K+ yellowish turning orange-red and forming star-shaped clusters of needle-like crystals under microscope (norstictic acid)
MEDULLA: white
ALGAE: green
APOTHECIA: ~1 per areole, sunken, disk black, often densely tan pruinose, epihyenium brown, hymenium clear, hypothecium clear, asci K/I- thickened tip, paraphyses narrow & anastomosing & strongly moniliform
SPORES: 8 per ascus, elliptical, smooth, around 20-25 × 12-14 µm, clear, simple

Clear ID based on norstictic acid, spore size, moniliform paraphyses, brown epihymenium. Apparently quite common in southern Caifornia mountains.


at 10x
at 30x
apothecial section, in water, at 100x
apothecial section, in water, at 100x, cross-polarized
apothecial section, in K, at 100x, after a few seconds
apothecial section, in K, at 100x, after a few minutes
norstictic acid crystals, in K, at 1000x

Proposed Names

87% (1)
Used references: Nash’s Sonoran Flora
Based on microscopic features
Based on chemical features: norstictic acid

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= Observer’s choice
= Current consensus


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