Hello Simon.

A very difficult type that is rarely encountered and it is even rarer to find it on a Pezizale. It seems that some spores have a spot on the more rounded side and that the asci have more than two or three spores. Is this correct?

Michel.

Hello all

what I would like to add

I have consulted various literature.

Lundqvist 1980
Doveri 2006
Breton & Faurel 1967 Mycorhynchus
and others

At the beginning I liked P. arvernensis. However, the rostrum is described much shorter and the substrate is dung.

P. marchalii was also a candidate. Here, however, the perithecium is much broader and the spores are also less broad.
In addition, the colour of the rostrum is much darker, also on dung.

The substrate of my find gives me a big headache. Is it possible to equate urinophilous with coprophilous? Both substrates have a greatly increased nitrogen content. Or do I have to look for the mycoparasitic species?

Greetings, Simon

Hello Michel

yes, I would see it the same way.

I'm not sure if I've seen Asci. I could not colour the ascus wall of the spore clusters.
The number of spores per asci gave me the impression that there could be 4 or slightly more.

Simon

Yes, some coprophiles can be found on places wet with animal urine.
I also went to marshalii, and the differences you point out do not shock me because by rereading your description the measurements you give are within the measurement range of several authors.

Hello Michel

thanks for your opinion.

I have already exchanged views with other people before posting in the forum. That's when the species P. marchalii came into play. At least something similar.

I'll take a closer look at P. marchalii again.

Simon

Hello Michel

Perhaps I made a mistake in my first description of my find.
I stated the dimensions of the perithecium as length (height) x width.
In the studied literature, the length (height) is not given much importance.
Doveri 2006 speaks only of diameter (width)
In my new measurements and review of my notes, I focussed on the diameter of the perithecia.

About the substrate:
In the Encyclopedia of Mycology (2021) there is a very interesting report on Pyxidiophora by Danny Haelewaters.
It mentions that various experiments have led to the conclusion that most Pyxidiophora species are mycoparasitic or at least thrive better in association with suitable fungi (p. 275).
For this reason, the question of the substrate is no longer so relevant for me.

Literature references (measurements) for P. marchalii

Rhynchomyces marchalii Sacc. in Marchal, Bull. Soc. R. Bot. Belg. 24(1): 60 (1885)

Perithecium:
Length 145-160 x width 110-125

Rostrum:
length 225-265 x width 35-45

Spores:
Length 65-70 x width 5.4-5.6

Mycorhynchus marchalii, in Breton & Faurel 1967 RevMyc 32(4) 1967

Perithecium:
Length 145-160 x width 110-125

Rostrum:
Length 225-265 x width 35-45

Spores:
65-70 x 5.4-5.6

Breton & Faurel emphasise the width of the perithecium in their key.
The first question under 1 is Perithecia up to 100 or larger. If you answer this question with up to 100, which is clearly the case with my fruiting bodies, 3 species remain.

These are

M. petchii
M. arvernensis
M. schotterianus

Mycorhynchus marchalii (Sacc.) Mig., in Trans. Br. mycol. Soc 68 (3) 329-340 (1977), Hawksworth & Webster

Perithecium:

110-125 (diameter)

Rostrum225-265

Spores:

65-70 x 5.4-5.6

Pyxidiophora marchalii, in Doveri & Coué 2006

Perithecium:
Diameter 110-125

Rostrum:
Length 250-320

Spores:
fusiform, sometimes with a filiform base, 65-70 x 5.5-5.6

Key from Doveri:

Question 1 deals with the substrate. I went both ways

Doveri combines the question on perithecia width under 4 with the length of the spore

spores longer than 65 and perithecium diameter wider than 100 to 5
or, spores shorter than 65 and less than 100 in diameter to 6.

The average spore length in my case is 65.10. So answers 5 and 6 are possible. If you add the diameter of the perithecia, you get 6.
P. petchii, P. grovei and P. schotteriana are worth considering, but they also leave many questions unanswered and do not really fit. Perhaps P. grovei comes closest, but the spores are too narrow.

Own measurements: according to notes

Perithecium diameter (width):

86
87
74
76
83
81
84
82
82
76
88
86
80
85
80
94
88
80
57
97

n=20 Average 82.3

Rostrum length:

236
297
238
214
206
220
286
293
243
270
318

Spore, width measured without gel cover:

71.71 x 6.25
71.00 x 5.74
58.42 x 5.66
66.32 x 6.83
64.46 x 5.23
61.00 x 5.86
64.13 x 5.72
58.94 x 6.82
67.50 x 6.41
65.34 x 7.35
67.23 x 6.43

n=11 Average width 6.21

Own measurements newly measured with piximeter 30.12.2023

Perithecium diameter (width)

90
99
91
95
78
109
107
74
80
102
110
76
83
72
81
87
99
75
80
82

n=20, average 88.5

Rostrum length, width at the base, width at the apex (below the taper)

233 - 39 - 16
300 - 43 - 16
207 - 34 - 18
212 - 47 - 18
209 - 35 - 15
211 - 44 - 16
235 - 35 - 19
221 - 46 - 19
158 - 45 - 19
300 - 38 - 17
302 - 38 - 16
288 - 38 - 21

I have been studying P. marchalii intensively over the last few days and weeks.
For the following reasons I am of the opinion that it cannot be P. marchalii.

Perithecia diameter on average from all measurements 85.4 ,n=40 and thus clearly smaller than P. marchalii 110-125

Spore width 6.21 , clavate/fusiform (P. marchalii 5.4-5.6, fusiform)

I wish you a good start into the new year

Simon

Thank you for this study and all these very interesting details. Indeed, it is undoubtedly a different species than the one we talked about in previous messages. This is a genus that we encounter very rarely and I don't have a lot of knowledge of all the species.



Best wishes 2024.