Caloplaca ulcerosa Teloschistaceae
Caloplaca ulcerosa

Growth type crustose
Chemical results: Thallus and soredia K-, apothecia K+ crimson
Identification: Bryan Edwards, Vince Giavarini

Scarce, on nutrient enriched base-rich bark of well-lit, mature trunks. Most frequent on Elm, Sycamore and Ash.

Thin greyish-white thallus with grey to pale yellow-green soralia bursting from blister-like craters. Scattered apothecia with bright orange discs, margins becoming excluded. Spores 8-12 x 4-8 Ám, septum 3-6 Ám wide. Paraphyses with swollen tips. Microscope photograph below.

The yellow apothecia in the photographs are Caloplaca phlogina


Caloplaca ulcerosa


Caloplaca ulcerosa

Microscope photograph
Caloplaca ulcerosa
Caloplaca ulcerosa
On Oak and Ash. Upton Park and Holton Lee, Dorset. January and March 2013

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