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15-12-2017 15:20


Dans le même xérobrometum (pelouse calcicole xé

14-12-2017 11:51

Per Marstad Per Marstad

3-8 mm in diameter, black, sp. 14-15 x 7-8 my, asc

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Castillo Joseba Castillo Joseba

En Phytolaca americana, me mandan el material sec

14-12-2017 11:51

Per Marstad Per Marstad

3-8 mm in diameter, black, sp. 14-15 x 7-8 my, asc

13-12-2017 20:24


J'ai trouvé hier, dans un xérobrometum (pelouse

14-12-2017 00:05

Valencia Lopez Francisco Javier

Hola a todos/asEstas Plicarias están recolectadas

13-12-2017 22:32

Pérez del Amo Carlos Manuel Pérez del Amo Carlos Manuel

Hola amigos, Pongo datos de una Otidea que encont

07-12-2017 22:53

Rubén Martínez Gil Rubén Martínez Gil

Hola a todos. Subo unas fotos de un asco que hemo

12-12-2017 06:24

Ethan Crenson

Hello all,Yesterday in Queens, New York City I fou

12-12-2017 17:03

Ethan Crenson

From New York City.  The perithecia are immersed

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Phomatospora on Urtica
Chris Yeates, 04-10-2017 22:38
Chris YeatesBonsoir tous
I recently collected some Urtica stems at the edge of a dense "jungle" of Rubus idaeus which I have been studying regularly for several years. Careful examination under the stereo microscope revealed a Phomatospora species. Under oil immersion it was clear that the spores had wavy, longitudinally striate walls.
Looking at the key to North American Phomatospora spp. in Margaret Barr's paper in Mycotaxon 51 p.217 she indicates two species with longitudinally striate spores: P. berkeleyi and P. striatispora. The spores of my collection are too small for the former and to my mind rather the wrong shape, nor do any have the "pulvinate terminal appendages" which Barr talks of.
Accordingly I am inclined to call this Phomatospora striatispora, although the spores are towards the bottom range of Barr's measurements (which she admits were based solely on the type collection). Alick Henrici has collected this from Kew Gardens, again on Urtica; as far as I know this is the only previous UK collection.
If anyone knows Phomatospora striatispora or has any comments to make I would be grateful. (The PDF will zoom up to at least 300% without pixellation)
Jacques Fournier, 05-10-2017 09:59
Jacques Fournier
Re : Phomatospora on Urtica
Bonjour Chris,
118 species of Phomatospora are listed in Index Fungorum. They typically have longitudinally striate ascospores. Some are dubious, most are poorly documented, thus it's not an easy task. The only species occurring on Urtica I am aware of is Phomatospora feurichiana Kirschst., collected in Switzerland. Its ascospores are 8-11 x 3-3.5 µm, a bit small for you, sorry.
Good luck!
Bernard Declercq, 06-10-2017 14:34
Bernard Declercq
Re : Phomatospora on Urtica
Bonjour Jacques,

Nous avons des collections de P. berkeley sur Urtica ici en Belgique. Mais la détermination est peut-être fautive. Comment faire la différence entre P. berkeley et P. feurichiana?
Merci d'avance pour ton aide.

Chris Yeates, 07-10-2017 02:19
Chris Yeates
Re : Phomatospora on Urtica
Like Bernard, in the UK (as well as records of P. dinemasporium, both anamorph and teleomorph) we have quite a few P. berkeleyi records on Urtica:


Jacques Fournier, 07-10-2017 19:19
Jacques Fournier
Re : Phomatospora on Urtica
Hi Chris,
you made it clear that a Phomatospora referred to P. berkeleyi is frequently collected on Urtica. The point is that there is some confusion about the delimitation of P. berkeleyi.
Spores dimensions are not given in the protologue of Sphaeria phomatospora, Saccardo gives 6-8 x 2-2.5 µm for P. berkeleyi, without mention of appendages. To follow Barr's concept, spores are 7-10.5 x 2.5-3.5 µm, with appendages.
This involved several different interpretations of P. berkeleyi and I think this name should be used with reservations until the type material is revised. Host specificity is often suggested in Phomatospora but difficult to assess when identification of species is confused.
The type collection is from UK, on potatoe stems in March, thus maybe you can solve the problem by finding a fresh collection of this fungus!