Bisporella citrina (Yellow fairy cups)

Kingdom: Fungi
Division: Ascomycota
Class: Leotiomycetes
Order: Helotiales
Family: Helotiaceae
Genus: Bisporella
Species: B. citrina
Binomial name: Bisporella citrina
Synonyms: Octospora citrina, Peziza citrina, Calycina citrina, Helotium citrinum, Calycella citrina,
Common names: Yellow fairy cups, Lemon discos

Bisporella citrina is a wood-rotting ascomycete fungus that produces tiny yellow cups up to 3 mm across and 1 to 2mm tall. The fruiting bodies begin as spherical, closed globules, before expanding into a cup. The smooth, gelatinous, flat-topped or saucer-shaped disc cups are a lemon or bright yellow in colour. Their margins are paler. The cups can have a tiny stout, tapering stem and if present it is rarely more than 1 mm in length. 
Bisporella citrina fruits in groups or dense clusters on decaying wood that has lost its bark. The fruit bodies may be so numerous that their shapes are distorted by overcrowding.
It is a cosmopolitan species that is found in many countries.

Bisporella citrina .jpg

Bisporella citrina.jpg 

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