Observation 188024: Agaricus xanthodermus Genev.

When: 2014-11-10

Collection location: La Jolla, California, USA [Click for map]

Who: Jacob Kalichman (Pulk)

Specimen available

- pleasant phenolic odor.
- mature cap dia. to stem dia. ratio 8:1.

cap staining:
- entire cap generally staining vivid yellow.
- less vividly (more pale) closer to the disc, and with age.
- yellow stain developing more slowly with age (max brightness within 5 seconds max for young, max within 20-25 seconds for old).
- stains changing afterward through several minutes, becoming orangish (still vivid) near the margin and fading paler yellow away from it.
- cap staining is only on the white parts – i.e., those parts with less exposure to light. the grey-brown areas don’t stain yellow (including the white flesh just below the color).

annulus staining:
- annulus staining is weaker and oranger w.r.t. cap staining.
- strongest annulus staining is on the cogwheel edges.

stem staining:
- pale yellow.
- about 10s to max brightness.
- the famously vivid stem base staining only takes place at the bottom of the bulb, where the stem tapers down again.

- somewhat stretchy. medium difficulty to remove from stem.
- margin is thin (gentle tapering to the edge).

annulus ventral:
- inner part at the stem is stringy and “adnexed”.
- distal to that it’s smooth/solid, possibly splitting into a cogwheel.
- cogs’ ventral surface is smooth. dorsal surface is cottony.
- cottony the rest of the way out to the margin.

annulus dorsal:
- inner part at the stem is stringly and “upside-down decurrent”.
- the rest is smooth-cottony, becoming covered in spores.
- with age, the middle part presses into the stem.

Proposed Names

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Created: 2014-11-11 07:35:20 EST (-0500)
Last modified: 2014-11-13 21:04:25 EST (-0500)
Viewed: 21 times, last viewed: 2017-06-19 08:31:56 EDT (-0400)
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