Leucocoprinus birnbaumii
(Corda) Singer
Description:
This bright yellow mushroom, which grows singly or in small clumps and fades with age, is found in plant pots and occasionally in glasshouses. The cap surface is smooth but dotted with fine, easily detached scales, and often develops shallow, radial grooves near the margin. A tropical species that has been introduced into New Zealand.

Cap: 20-60 mm, convex to plano-convex, sometimes with a low umbo; colour: bright lemon­yellow to sulphur­yellow, fading with age. The surface is powdery, granular, or finely floccose, especially towards the centre. Margin translucent striate when moist. Flesh thin, yellow, and unchanging when cut.
Gills: free, crowded, thin. Pale yellow to whitish yellow. Edges smooth.
Stipe: 40-90x 3-6 mm, slender, hollow, fragile. Yellow, sometimes paler toward the base. Ring thin, fragile, often disappearing with age. Base sometimes slightly swollen.

Common name: Yellow Pleated Parasol.
Habitat: Potting mix, nursery stock, greenhouses, and indoor plants.
Substrate: Saprobic on rich organic matter.
Distribution: New Zealand wide.
Season: Thrives in warm, humid conditions.
Biostatus: Introduced.
Edible: Poisonous.
Spore print: White.
Macro images:
Leucocoprinus birnbaumii
Scale bar
Scale= 8.5 mm.
 
Leucocoprinus birnbaumii
Scale bar
Scale= 8 mm.
 
Leucocoprinus birnbaumii
Scale bar
Scale= 8 mm.
 
Leucocoprinus birnbaumii
Scale bar
Scale= 8 mm.
 
Hidden Forest
Forest Fungi