Observation 113227: Gymnopilus junonius (Fr.) P.D. Orton
When: 2012-10-11
No herbarium specimen

Notes: Tight group of large yellowy-orange mushrooms growing in wood chips near shrubs on a traffic island.
Caps up to about 11 cm across, with holes where something (slug?) had been eating them revealing dull yellowish flesh. The caps were a patchwork of orange-brown, yellow and white patches (maybe as a result of being nibbled?). They were convex but almost flat. A few drops of KOH on the cap turned very dark reddish brown.
The stems were fused together at the base and were pale at the top, had a distinct rust-brown ring peeling downwards and were covered in yellow fibres, especially towards the base. The specimens I brought home had stem measuring 5 cm tall, 1.2 cm diameter at top and about 1.8 cm at base.
The gills were yellowish-brown and slightly decurrent. They looked more orangey after being in the house for a few hours.
A fragment of gill tasted quite bitter. The mushrooms smelt pleasantly mushroomy.
Cystidia (not sure where on the gills they were from) were shaped like skittles with a little knob at the top.
The basidia were 4-spored. The spore print was a rich brown colour. The spores were more or less oval with roughened edges and surfaces, brown in Melzer’s reagent and measured 8-10 × 5-6 microns (based on sample of 60 spores, discarding highest and lowest measurements).


Caps growing in wood chips
Undersides with another view of substrate
Stems fused together at base
Descending ring and slightly decurrent gills
Rust brown spore print
Spores in Melzer’s x1000, neatly lined up with Paintshop
4-spored basidia x400 stained with Congo Red
Skittle-shaped cystidia, stained with Congo Red
Cap reacting to a few drops of 10% aqueous solution of Potassium hydroxide (KOH)

Proposed Names

81% (1)
Eye3 Eyes3
Recognized by sight: Colour, size
Based on microscopic features: Basidia, cystidia, spores
Based on chemical features: KOH reaction on cap

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Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
By: Martin Cooper (martincito)
2012-10-12 08:00:08 PDT (-0700)

Thanks Rocky, much appreciated.

By: Rocky Houghtby
2012-10-12 07:56:00 PDT (-0700)

Cool spore micrograph

Created: 2012-10-12 07:44:20 PDT (-0700)
Last modified: 2012-10-12 07:49:31 PDT (-0700)
Viewed: 50 times, last viewed: 2016-10-23 00:50:12 PDT (-0700)
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