Observation 145513: Amanita americitrina Tulloss nom. prov.
When: 2013-09-14
Collection location: Perry, Maine, USA [Click for map]
No herbarium specimen

Notes: Cap white with flat brownish patches (see last photo), 60 mm., umbo, yellowish over center, thin white flesh. Gills whitish, close. Stem hollow, whitish with skirted ring, 90 mm. × 8 mm. midheight. Bulb 24 mm. w x 20 mm. h. Smell radish like. KOH on cap negative. On ground in mixed woods. I thought this was Amanita bisporigera at first look but I think the patches on the cap and negative KOH reaction rule that out—not to mention the very thin flesh over top of stem, hollow stem and radish-like rather than sweet odor.

Images

367213
Brown on bulb
367214
367215
Gray under ring
367216
367217
Hollow stem and soft spongy bulb
367478
Brownish coloring of bulb
367479
Flat brownish patches on cap

Proposed Names

28% (1)
Used references: Amanita studies site
Based on chemical features: KOH on cap negative
57% (1)
Eye3 Eyes3
Used references: see comments below

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

Eye3 = Observer’s choice
Eyes3 = Current consensus

Comments

Add Comment
Yes, they don’t always turn color.
By: R. E. Tulloss (ret)
2013-09-17 16:55:44 PDT (-0700)

The first time I saw a color change on americitrina (still called brunnescens var. straminea on the WAO website), it was simply small radial dashes of lavender on a few mature specimens the day after Christmas on the border of South Carolina and Georgia. There are illustrations of this collection (from Hartwell Lake) on WAO.

The most dramatic color changes I’ve ever seen in the “lavendula-group” were the solid amethyst caps in cold rain at about 1 degree above freezing (Cape Cod foray several years ago) on a specimen of the hybrid taxon and a large spot of lavender on a stem of f. lavendula at a NAMA Regional Foray in western North Carolina (Wildacres).

In selecting a lectotype collection for f. lavendula it was necessary to read all the notes on each of Coker’s collections and find a set of candidate collections that clearly stated that lavender was present on the fruiting body. Clearly Coker collected material that had no lavender on it at all.

Very best,

Rod

Would this name
By: Terri Clements/Donna Fulton (pinonbistro)
2013-09-17 16:41:15 PDT (-0700)

apply also to a citrina that does not turn purple? I found two today that fit the A. bulbosa var. citrina description on your website—no purple yet. I’m leaving them on the porch overnight, expected low’s in the high 30’s to low 40’s. We had the same temps last night and these two show no signs of purple coloring but have pale yellow cap with brown patches, pale yellow skirt-like ring, whitish stem that is pale yellow above the ring, soft spongy bulb and radish-like smell.

Terri

It looks like someone called “Tulloss”…
By: R. E. Tulloss (ret)
2013-09-17 15:51:21 PDT (-0700)

is responsible for deprecating “brunnescens var. lavendula” on MO.

That guy prefers his provisional name americitrina. I suppose he must know what he is doing…

:)

R.

Very cool.
By: R. E. Tulloss (ret)
2013-09-16 13:32:38 PDT (-0700)

The purple color can appear anywhere. In the hybrid species, the purple can be deep amethyst. I have seen deep purple on the stem of citrina f. lavendula and lavender radial dashes on what I think may be the present species. I have never seen purple on the gills, but…Why not?

This is a fascinating group of taxa that is in the process of discovery and rediscovery right now.

It’s a cool thing to be there as the data is coming in, being processed, etc….and while the species are being separated in differenct ways (molecularly, by spore size/shape, etc.).

Very best,

Rod

This specimen
By: Terri Clements/Donna Fulton (pinonbistro)
2013-09-16 12:28:06 PDT (-0700)

was out on my porch overnight (frost warning). The next morning there was a slash of purple on the gills but nothing like that on cap or stem. I didn’t preserve this specimen but may be able to find another.

By the way, did you receive the 4 dried specimens I sent to you 2-3 weeks ago?

Terri

A second thought was that the species might be in the bisporigera group.
By: R. E. Tulloss (ret)
2013-09-16 12:08:15 PDT (-0700)

That group does contain at least one member that can have yellow over the disc. However, the gray material on the bottom of the edge of the partial veil is certainly unknown in the bisporigera group and is known in citrinoid taxa. So I’ll stick with my first suggestion.

You might find this same entity (after a near freezing night) with lavender on the cap and or stem. This can occur as a smear of color or as radially dashes of color…if this is indeed brunnescens var. straminea. (It’s not brunnescens and it needs a name at species rank. There’s a plan for that.)

Rod

This could be A. brunnescens var. straminea
By: R. E. Tulloss (ret)
2013-09-16 12:02:25 PDT (-0700)

which is apparently a lavender staining citrinoid species. The name was provided by Gilbert (whose knowledge of North American taxa was not very complete even for the 1930s).

If you can obtain material of this, Terri/Donna, I’d be interested in looking at a specimen.

Very best,

Rod

Created: 2013-09-15 13:56:51 PDT (-0700)
Last modified: 2013-09-17 16:35:09 PDT (-0700)
Viewed: 61 times, last viewed: 2016-09-06 07:19:28 PDT (-0700)
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