Please do not re-click a link while waiting for a page to load. (It’s slower and degrades site speed for all users.)
To get images for machine learning, see MO Images for Machine Learning

 

Notes:
Two fragile fruiting bodies growing at a base of a deciduous tree (probably a hickory), with oak, beech and maple in the immediate vicinity. Pale lemon-meringue yellow caps (or light yellow-cream?) with striations of up to 0.35-0.38R and deeply buried stipes (20-30% of stipe length). With regard to the latter aspect, Rod commented: “Placement in the Penetratrices is possible. Apparently a yellow pigment did evolve within the Penetratrices. Since the Penetratrices includes mostly non-yellow species, I think the argument can be made successfully that the yellow pigment did not come from a Caesareae-like ancestor of the Vaginatae.”
The larger mushroom had a cap of 5.7×5.2 cm in width. The stipe was 13.5 cm long (the tip might have been broken off), 6 mm wide at apex, 8 mm wide at base.
The smaller mushroom had a cap of 3.5 cm in width. The stipe was 10.8 cm long, including the broken off tip with a volval sack that was recovered at the time of collection but then lost, 4 mm wide at apex, 6 mm wide at base.
The spores are globose to subglobose. I didn’t measure them yet, but taking a reticle to a few large spores at x400 without a mounting agent gave measurements of 10-12 microns.
This collection was preserved for RET.

Images

Larger fb
Larger fb
Larger fb
Larger fb
Larger fb
Smaller fb
Smaller fb
Smaller fb

Proposed Names

ret
82% (1)
Based on chemical features: Molecular identification by partial nrITS and partial nrLSU

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

= Observer’s choice
= Current consensus

Comments

Add Comment
Hello, Rod
By: I. G. Safonov (IGSafonov)
2018-08-21 23:08:02 CDT (-0400)

I checked what the weather was like in July of last year in Titusville, NJ, – that’s where the park is. It had rained there on July 13 & 14 of 2017, so I think this collection grew in response to that precipitation. It hadn’t rained there again before I picked these. This means that the pigment was not washed out by the rain, and the dirt on the caps is yet another bit of evidence in support of dry weather during development & maturation. These fruiting bodies grew at the base of the tree in good shade, so no bleaching out by the sun. It’s possible that the pigment could have faded over time due to heat & humidity, but my guess is that at no time the color was any shade of brown; it was always yellow, just darker yellow at the outset.
I understand there is no question about the DNA sequences themselves… unless a mistake was made during sampling/sample manipulation during sequencing, meaning that the sequences belong to a different collection (were there any other known justicei collections in that sequencing batch?). I am not suggesting a mistake was made to explain the discrepancy in the cap color; however, looking at other photographs of sequenced justicei on MO and also on your website, it appears that the typical cap color is some shade of brown. The only collection that comes close to mine in terms of the cap color is Geoff Balme’s obs 280813 (when photographed in situ); however, when photographed by Geoff at home, the color is brown. The cap color of my collection (i.e., this observation) under any lighting conditions is most similar to that of A. williamsiae (e.g., obs 289538).
I think once you receive all the sequences for this batch of samples and everything hopefully makes sense in terms of matching sequences to their respective collections, this one will turn out to be justicei after all. If the cap color is indeed so variable in this taxon, field identification is going to be nearly impossible. :-)

With all our rain, I suppose that the pigment has been diluted on the cap.
By: R. E. Tulloss (ret)
2018-08-21 09:56:53 CDT (-0400)

There is no question about the DNA sequence.

We will have to reassess the earlier post that you cited in your comment. It seems we have not sent it out for DNA sequencing we need to do that.

Very best,

Rod

With all our rain, I suppose that the pigment has been diluted on the cap.
By: R. E. Tulloss (ret)
2018-08-21 09:35:23 CDT (-0400)

There is no question about the DNA sequence.

We will have to reassess the earlier post that you cited in your comment. It seems we have not sent it out for DNA sequencing we need to do that.

Very best,

Rod

Thanks for the “field note” details, Igor.
By: R. E. Tulloss (ret)
2018-08-20 22:35:25 CDT (-0400)

Very best,

Rod

This is Amanita justicei nom. prov. with very good support from both…
By: R. E. Tulloss (ret)
2018-08-20 22:33:33 CDT (-0400)

the nrITS and nrLSU genes. I believe this is the second known collection of the species from New Jersey. Both collections were made by members of the New Jersey Mycological Association. Congratulations and thanks.

Very best,

Rod

The cap is much too yellow for penetratrix.
By: R. E. Tulloss (ret)
2018-05-18 14:39:38 CDT (-0400)

Also, recent recheckng of the percentage of the stipe inserted in the ground in penetratrix, penetrans, and semiobruta (all nom. prov.) show that the portion buried in the ground approaches 50% of the length of the (long) stipe.

Could this be another species that turns out to be related genetically to the penetratrix group—-A. williamsii nom. prov.?

Very best,

Rod

Sampled for DNA sequencing today.
By: R. E. Tulloss (ret)
2018-05-18 14:36:08 CDT (-0400)

Thanks again, Igor.

Rod

Same as…
By: I. G. Safonov (IGSafonov)
2018-01-03 21:29:27 CST (-0500)

obs 143047? Yellow caps, almost identical dimensions and striations/cap radius ratio.

Herbarium Rooseveltensis Amanitarum (RET) has received specimen.
By: mcmacher
2017-11-02 12:27:39 CDT (-0400)

We have received the dried specimen. Thank you. It is being accessioned in Herbarium Rooseveltensis Amanitarum as RET 801-7.