Pertusaria amara Ochrolechiaceae
Lepra amara (Pertusaria amara)

Growth type crustose
Chemical results: Soralia and medulla K-, C-, KC+ violet (fleeting), P+/- red, UV-. Soredia taste test positive for oxalic acid (persistent, very bitter)

Common on deciduous trees, occasional on conifers and over moss on rocks

Very variable. A grey thick or thin thallus, slightly zoned at margins. Punctiform soralia are +/- regularly scattered over surface with whitish farinose soredia. Apothecia very rare, asci 1-spored.

Similar: P. albescens is more zoned at margins, KC-, taste test negative

Pertusaria amara

Pertusaria amara
Pertusaria amara
On Oak. Holton Lee, Dorset. October 2012

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