Agyrium rufum (Pers.) Fr.

A non-lichenized fungus (or with a few algae), occupying patches of wood of branches, producing a whitish, thallus-like stain; apothecia red, aging to brown or blackish, usually raised up on a short welt of the substrate; rim thin and receding; disc strongly convex; upper hymenium with a diffuse red pigment; hypothecium colourless; paraphyses thin, net-like with numerous branches, the branches often joining, especially in upper portions, embedded in gel; asci club-shaped, with a thickening at the tip that is always wider than high; spores 8 per ascus, colourless, without septae, often with a single large oil droplet, 10-15 × 6-8  µ.

Reactions: All spot tests negative.

Contents: No lichen substances reported.

Habitat: Hard wood, usually on branches. All forested elevations.

Similar Species: Biatora globulosa has jet black apothecia and green pigments in the hymenium. Catillaria erysiboides grows on soft wood of logs and has 1-septate spores. Lecidea coriacea grows on soft wood and has more than 8 spores per ascus.

Specimens: Goward 96-742.

Local Status: Common and widespread.

Notes: Though not or only weakly lichenized, A. rufum is traditionally treated among the lichens owing to its thalline appearance and close ancestry with Placynthiella and Trapeliopsis.