Green elfcup

Chlorociboria aeruginascens

''Chlorociboria aeruginascens'' is a saprobic species of mushroom, commonly known as the green elfcup or the green wood cup because of its characteristic small, green, saucer-shaped fruit bodies. Although the actual fruit bodies are infrequently seen, the green staining of wood caused by the fungus is more prevalent.
Green Elfcup - Chlorociboria aeruginascens Greenish blue cup fungi with off-centered stems.  They were about 5 mm wide. 

This species contains a quinone pigment called xylindein, which is the reason for the characteristic bluish-green stain that occurs on wood that's infected by this species.

Habitat: Rotting wood Chlorociboria aeruginascens,Fall,Geotagged,Green elfcup,United States. Chlorociboria,fungus

Appearance

This species has apothecia that are usually attached laterally, often less than 0.5 cm in diameter, collapsing laterally and becoming rolled inwards when dry. The outer tissue layer of the apothecium, known as the ectal excipulum, has a delicate tomentose surface composed of hair-like, straight or sometimes coiled, smooth hyphae. The stipe is typically less than 3 mm long, with a central or eccentric attachment to the apothecia. Spores are roughly spindle-shaped , smooth, and 5–8 by 0.7–2.8 µm. Apothecia grow on bark-free wood, especially oak, part of which at least is stained greenish by the mycelium. The abundant paraphyses, which may be entwined, are 55–95 by 1.5–2 µm, filiform, and septate with an unswollen, unbent apex that often extends beyond the level of the asci tips.

The species is distinguished from the closely related ''C. aeruginosum'' by having smaller spores. Although some authors have in the past failed to recognize any appreciable differences between the two species, Ramamurthi and colleagues note that not only are the spore sizes different, but ''C. aeruginascens'' have smooth tomentum hyphae, in contrast with the roughened hyphae of ''C. aeruginosum''.

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Taxonomy
KingdomFungi
DivisionAscomycota
ClassLeotiomycetes
OrderHelotiales
FamilyHelotiaceae
GenusChlorociboria
SpeciesC. aeruginascens