Collection location: The Hill, University of Tennessee, Knoxville, Tennessee, USA [Click for map]
35.9578° -83.9265° 290m
On soil in shaded lawn.
Edit: CCB 08/08/13
ITS BLAST Panaeolus foenisecii (ITALY)-99%; Panaeolus rickenii (ITALY)-97%; Panaeolus fimicola (ITALY)-97%; Panaeolus acuminatus(ITALY)-97%; Panaeolus antillarum (ITALY)-97%
|I’d Call It That||3.0||0.00||0|
sum(score * weight) /
(total weight + 1)
collections from CA with microscopy, in my limited experience the microscopic characteristics have not proven to be variable yet (Not to say they won’t with time & study). Murill’s and Smith’s descriptions of the two species are useless. Gerhardt did include the epicutis cell size in his descriptions.
P. foenisecii – Epicutis zellig, Zellen ca. 15-25 um breit.
P. castaneifolia – Epicutis zellig, Zellen ca. 25-35 µm breit.
I think its well established that no one knows how to resolve this yet, hence why I suggest comparing numerous collections thoroughly. Your observation is really close to that point too. More info on the oil drops and size of the epicutis cells would help.
“So far known only from the type locality in the United States” and since we are in the type locality (at least in the Southeastern US), I guess its not unreasonable to postulate that some, many, or most if not all of the Pan foe’s that we’re finding are actually castaneifolia. However, Gerhardt chose to recognize P. castaneifolia as a distinct taxon based on some very slight (and possibly highly variable) characters that he observed after looking at a single collection.
With some of these yard-mushrooms (like C. molybdities, Conocybe apala, etc.) that have greater opportunities to travel across oceans with humans it would be interesting to find out whether something that might be “castanifolia” represents a phylogentic species (are they genetically distinct from foenisecii?) and whether they represent a biological species (can they interbreed with foenisecii?).
The characters used to make a distinction here may be variable, and are based on a single collection, however, some of these difference described in the literature are:
-Panaeolina castanifolia should have a distinctive strong odor and unpleasant taste (this character was reported in Murrill’s description but obviously not confirmed by Gerhardt’s single examination of dried material)
-Panaeolina castanifolia should have a slightly more robust fruitbody, the flesh a little thicker
-Panaeolina should have slightly larger epicutis cells (on average), however, measurements are not provided in Gerhardt’s description for P. castanifolia and ironically, they are not provided in description for foenisecci either!
-spore sizes overlap, P. castaneifolia: 13-17 (19) x 7.5-9 (10) microns compared with (11.5) 14-17 (22) x (7.5) 8.5-11 microns for feonisecii, but Gerhart describes the spores as slightly more narrow. Gerhardt also describes the germ pore as “not signficantly brought forward,” I have interpreted this to mean “not oblique or only slightly so??” or maybe there is a problem with the translation “Keimporus meist nicht vorgezogen.”
-basidia of P. castanifolia tend to be more consistently 4-spored.
-oil drops may not be a consistent character as age of the spore seems to related to presence of oil droplets, but Gerhardt describes P. castaneifolia spores as “usually” without an oil droplet (again, this observation was
based on a single collection).
With the P. castaneifolia description? I mean beyond basidia, such as size of the epicutis cells and presence/absence of oil drops?
Created: 2013-06-07 10:03:16 AEST (+1000)
Last modified: 2013-08-09 07:26:53 AEST (+1000)
Viewed: 106 times, last viewed: 2018-01-16 01:08:38 AEST (+1000)