When: 2008-12-07

Collection location: Sebastopol, Sonoma Co., California, USA [Click for map]

Who: Darvin DeShazer (darv)

No specimen available

I know this is the bolete eater species of Hypomyces, but it keys to this species, which is common in the area. It was on several Boletes within 3 meters of these Amanitas. Also H. hyalinus distorts the mushrooms and the growth of this Hypomyces is different and leaves the mushroom intact.

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Still only the imperfect stage.

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Recognized by sight: Is this an albino? The warts are on top of the white.
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Recognized by sight

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OK – now I’m confused.
By: Darvin DeShazer (darv)
2008-12-11 23:14:01 CST (-0600)

More info for 12/10/08.
I returned to the growing site and collected a fruiting body covered by Hypomyces. Using a lead from Rod Tulloss, Rogerson and Samuels (1994) said that Amanita muscaria from California has been parasitized by Hypomyces hyalinus. However it also stated that no anamorph was known. When I looked at the microstructures, all of the spores found were from an anamorph and NONE matched the photos or description of the ascospores.

Since Boletus subtomentosus was nearby and covered with Hypomyces, I looked up Hypomyces chrysospermus in and Rogerson and Samuels (1989) had a key to the anamorphs and well as a key to the ascospores. The anamorph key went straight to Hypomyces chrysospermus but the pictures in Mycologia did not supported it.

Currently, it is unknown what’s going after this fly agaric! I did find a reference to Hypomyces chrysospermus on Stropharia sp. (Ola’H, 1970), but not on Amanita.

A couple of the other fruiting bodies were left in the field and hopefully they might develop the perithecia and supporting proof of the ascospores.

Ola’h, Gyorgy-Miklos. 1970. Stropharia sp. (section Mundae Fr.) parasite par Apriocrea chrysosperma var. strophariae (Sydow) Ola’h n. var. Revue de Mycologie 35 (2-3): 141-149.

Rogerson, Clark T. and Gary J. Samuels. 1989. Boleticolous species of Hypomyces. Mycologia 81(3): 413-432.

Rogerson, Clark T. and Gary J. Samuels. 1994. Agaricicolous species of Hypomyces. Mycologia 86(6): 839-866.

note hyphal mass near the base…
By: R. E. Tulloss (ret)
2008-12-11 08:48:50 CST (-0600)

Taking into account Darv’s other photographs of white growth on a muscaria, I’d say that it is probably a Hypomyces. In early stages of attack, several species of Hypomyces that I have seen start to cover a mature fruiting body with somewhat fluffy white hyphae. I have seen this in H. lactifluorum on Russula, for example.

In the east we are used to see H. hyalinus on species (especially) of Amanita sect. Validae…particularly A. amerirubescens Tulloss nom. prov.
I do not recall seeing such hypomycized specimens that were mature. Apparently,
amerirubescens is commonly attached in an early stage of expansion when the amanita tissues are quite dense. This may not be a good predictor of what would happen if H. hyalinus were to attack a mature specimen of amerimuscaria.

I think we may have an open issue for the moment. Darv, did you find mature “flasks”? Are there more of these critters still maturing at your site? Do you know if Gary Samuels would take a look at the material? It seems to me that Heather Hallen was once involved in trying to identify host and parasite using molecular methods.

Are the spores from asexual or sexual reproduction?

Very best,


was it soft like a hypomyces attacked amanita?
By: Debbie Viess (amanitarita)
2008-12-07 22:03:33 CST (-0600)

otherwise, it could be a white variety, altho I have never seen one coastally in CA before, just in OR and the Sierra.

By: R. E. Tulloss (ret)
2008-12-07 20:07:19 CST (-0600)

I think there’s something growing on it. I believe that Hypomyces hyalinus has been reported from western specimens of “muscarioid” taxa.