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crust lichen, on granite
THALLUS: small convex areoles, gray to light gray, dull, K-
MEDULLA: white, K/I-, K-
APOTHECIA: cryptolecanorine, rim same as thallus, aphithecium filled with POL+ whitish not dissolving in K; epihymenium brown, some POL+ white smalll granules insol in K; hymenium clear, K/I+ blue; hypothecium clear, K/I+ weak bluish; paraphyses submoniliform to moniliform, at least 3 often more than 4 swollen cells toward end, width (3.2)4.1+/-0.4(4.6) µm (N=10), K/I weak gold; asci thick I- tip with hole in it showing blue walls through it if viewed end-on, clavate
SPORES: 8 per ascus, elliptical, clear, simple, smooth, often K/I+ red on either end, (17)20+/-2(25) x (10)11+/-1(15) µm (Q=(1.4)1.8+/-0.2(2.2)) (N=13), walls (0.7)0.9+/-0.2(1.2) µm (N=11)

There are a few grayish species much like this one, including A. fumosa and A. cyanescens, and A. caesiocinerea. The latter two hould be distinctly bluish; the former should have apothecial rims darker than thallus. Some also differ in epihymenium color, and all differ subtly in conidia length, which I never even measured.


at 30x
at 10x
apothecial section, in water, at 100x
Apothecial section, in water, at 100x, cross-polarized.
Ascus and spores, in K/I, at 1000×. Notice the uniformly lightly-stained ascus tip — this is typical of Aspicilia-type asci.

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Used references: Nash’s Sonoran Flora
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