Observation 33995: Hymenogaster subalpinus A.H. Sm.
When: 2010-02-22
No herbarium specimen

Notes: I first noted this on Feb. 13 at the NATS forage to Paul Bishop’s, but was unsure of the designation. Spoke to Adrien Beyerle, who stated the only species he knew of with an olive-tinted gleba was something siccigleba. The only hypogeous species I have been able to document is Mycolevis siccigleba, hence this identification. Sporocarps are up to 2 inches in diameter, often subglobose to somewhat flattened; with a relatively thick peridium and abundant pubescent hairs on the peridium, often with soil adherring strongly; with splotchy greenish-yellow highlights; columella not seen in my collection; loculate, locules tiny and appear widely scattered through the gleba; odor similar to very mild Hymenogaster or rotting fruit, somewhat foul to my nose; gleba with tints of light blue-green color or chrysoprase (a semi-precious gemstone also known as nickel bloom); typically found in late January or early February at Paul’s; parasitized by some form of insect as shown in the accompanying photos. I have collected this many times in the past 20 years at Paul’s but never took a close look at the peridium, and never took photos to document it. Am currently drying several specimens. Positive identification will need to wait until identification has been confirmed by experts in the field.

Proposed Names

7% (2)
Recognized by sight
86% (1)
Eye3 Eyes3
Used references: Identified by Matt Trappe, who identifies all North American Truffling Society collections at this time. Matt suggested the odd coloration was due to the specimens being “slightly over the hill”.

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Eye3 = Observer’s choice
Eyes3 = Current consensus


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Left message with Matt Trappe’s answering machine …
By: Daniel B. Wheeler (Tuberale)
2010-03-03 16:12:54 PST (-0800)

but have heard nothing back from him.

Another observer here has suggested this identification is unlikely. I’m willing to listen to other suggestions. However, the reality is only one species currently is known to me (and Adrian Beyerle) that has a greenish to transluscent-green gleba: Mycolevis siccigleba. If confirmed, this will be the second confirmed identification of this species since Dr. Alexander H. Smith first reported it from Idaho in 1955, I believe.

With hypogeous fungi, the question of abundance always is associated with the skill of the identifier. This fungus has aromas similar to Hymenogaster, which is too frequently encountered to warrant much serious examination, even among North American Truffling Society members. Ignoring what appears to be locally common is another failure, IMO, of professionaly mycologists. This collection proves the coloration of the peridium, abundant pubescent hairs of the peridium strongly adherring to soil particles (I literally had to scrape some off), and the greenish-tint to the gleba. All that remains is to positively identify the spores.

Let’s ignore the question of spores, though, for the moment. The only other hypogous species with somewhat greenish gleba (but not the same characteristics of the peridium at all) is Hysterangium, which this definately is NOT. Most Hysterangium can be quite abundant locally: I have found several hundred sporocarps in a single square foot at a tree farm near Molalla, Oregon. The fibrous mycelium associated with Hysterangium is not present with these sporocarps. While soil adhers strongly the peridium, it is not necessary to physically pull apart the tough mycelium to get at the sporocarps of this observation.

So I will tentatively stick with my identification (and that of Adrian Beyerle) for now until and unless another possible species is presented to replace it.

There is one oddity to this versus the description of Smith regarding Mycolevis: the sporocarps are not at all like styrofoam in texture. I would describe the texture of this observation as more closely resembling crisp apple. The sporocarps are also not especially light-weight: more like Hymenogasters, which are riddled with locules of varying sizes throughout the gleba, and often have remnants of columella present.

Created: 2010-02-22 17:11:05 PST (-0800)
Last modified: 2010-04-25 12:02:35 PDT (-0700)
Viewed: 336 times, last viewed: 2016-10-27 01:09:22 PDT (-0700)
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