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Nemania gwyneddii (Whalley, Edwards & Francis) Pouzar.
Stromata superficial, ellipsoid-elongate, 11-25 mm long x 3-4 mm broad
x 0.6 mm thick, weakly carbonaceous; surface blackish brown to dull black, with
inconspicuous perithecial mounds; interperithecial tissue soft, dark grey, inconspicuous;
margin narrowly effused, black.
Perithecia subglobose, 0.5-0.6 mm diam.
Ostioles minutely papillate, black.
Asci fragmentary, not measured, short-stipitate according to the type
description, with apical apparatus amyloid, urn-shaped to cylindrical,
5-7 µm high x 3-4 µm broad.
Ascospores 20-26 (-29) x
7-11 µm, pale brown, ellipsoid-inequilateral with broadly rounded ends, sometimes with
one end pinched, with a short, fairly conspicuous germ slit 3.5-4 µm long on
the more convex side.
Specimen examined: FRANCE: Ariège (09): Rimont, Saurine,
28 Apr. 2001, JF-01082, on wood of Fraxinus excelsior.
Notes: This specimen was identified to N. gwyneddii
relying on the particularly large dimensions of apical apparatus and
ascospores. Nemania gwyneddii is a very rarely recorded species, previously only
known from the type collection in Wales, U. K., (Whalley et al.,
1983). Unlike this material which was said to be "somewhat immature
and scanty" by Ju and Rogers (2002), our collection consists of two overmature
and depauperate stromata in which only three perithecia were found to be ascigerous.This
could explain the apparent discrepancy between ascospore shape in both collections,
more slender in the type collection than in ours.
Nemania gwyneddii is macroscopically much like N. serpens,
but is characterized by a massive amyloid apical apparatus and large pale brown
ascospores averaging 25 µm long with a very short but fairly conspicuous germ
slit on the more convex side. Petrini and Müller (1986), when
examining the type collection, reported this germ slit as spore-length, without
mentioning its situation on the more convex side.
The type material of N. gwyneddii was collected on wood of Fraxinus
and on unidentified wood (Whalley et al., 1983). Our collection is likewise
on Fraxinus, which could indicate a host-preference.
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