Observation 21579: Fuligo septica (L.) F.H. Wigg.

When: 2009-06-02

Collection location: Orinda, California, USA [Click for map]

Who: Richard Sullivan (enchplant)

No specimen available

This was growing on an oak stump in my yard in the Bay area. Last week I saw the same thing in the Sierra Nevada at 6,000 feet under firs.
I tried to examine the yellow omelette stuff under the microscope but even at 1000x I could only make out tiny circles. Later the blob dried out and the whole interior of it had turned into a material that felt like fine ash. Under the microscope this revealed itself to be a mass of cup shaped spores.

Species Lists


The wonderful omelette stage
The fine ash stage
Spores at 1000x
Spores at 1000x

Proposed Names

91% (2)
Recognized by sight

Please login to propose your own names and vote on existing names.

= Observer’s choice
= Current consensus


Add Comment
By: Clive Shirley (myxo)
2009-06-04 00:24:20 PDT (-0700)

I agree with Darvin these are dehydrated spore often seen in dried myxo collections or when left mounted under the microscope to long. Fortunately 3% KOH or even water soon rehydrate them.

Spore shape
By: Richard Sullivan (enchplant)
2009-06-03 13:05:56 PDT (-0700)

Hi Darv,
This is an interesting question. This was the dry spore mass, The stuff that felt like ash – No mounting fluid at all was used up to 1000X. So when I add a drop of water to the slide they immediately swell up into spheres, But they were naturally collapsed before that.

Concentration of liquid?
By: Darvin DeShazer (darv)
2009-06-03 01:35:15 PDT (-0700)

The spores should be round spheres. The cup-shaped spores look like round spores that have collapsed. This can happen if the mounting fluid is NOT isotonic. 3% KOH is OK to use, but 10% KOH will suck the water out of fragile spores and cause them to collapse and deform. You also might have stopped the growth before it could mature.

Photos of spores
By: Richard Sullivan (enchplant)
2009-06-02 18:59:10 PDT (-0700)

Created: 2009-06-02 18:49:18 PDT (-0700)
Last modified: 2009-06-02 18:49:18 PDT (-0700)
Viewed: 254 times, last viewed: 2019-01-29 01:05:04 PST (-0800)
Show Log