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Nemania effusa (Nitschke) Pouzar.
Stromata superficial, effused-elongate, 10-30 mm long x 4-10 mm broad
x 0.5-0.8 mm thick, weakly carbonaceous; surface dark brown to blackish brown,
with very conspicuous perithecial mounds, when immature coated with a beige
hyphal layer; interperithecial tissue whitish, soft; margin abrupt.
Perithecia
subglobose, frequently flattened, 0.4-0.6 mm diam x 0.4-0.5 mm high.
Ostioles coarsely papillate, conical, black.
Asci cylindrical, long-stipitate, the spore-bearing parts 50-65 µm
long x 5-7 µm broad, the stipes averaging 80 µm long, with apical apparatus
amyloid, inverted
hat -shaped, 2-2.5 µm high x 1.5-1.8 µm broad.
Ascospores
6-7.5 (-8) x 2.7-3 (-3.5) µm, pale brown, ellipsoid-inequilateral with broadly
rounded ends, 1-2-seriate in the ascus, with a very inconspicuous short germ
slit on the less convex side.
Specimen examined: FRANCE: Tarn (81): Sorèze, St. Jammes,
15 Jun. 2002, JF-02111, on decorticated wood of a dead standing trunk of Salix atrocinerea,
in a willow bog. Found immature and kept in a damp place until its maturation
in September 2002.
Notes: Nemania effusa differs primarily from other serpens-like
members of Nemania in its short and narrow ascospores. Ascospores
dimensions given by Granmo et al. (1999) are 6-9.5 x 3-4.5 µm, slightly
larger than reported elsewhere (Dennis, 1974; Pouzar, 1985b; Petrini and Müller,
1986; Ju and Rogers, 2002). Its dark
brown
stromata with very conspicuous perithecial mounds and conical black ostioles
also are fairly distinctive.
It is considered as rare in North America by Miller (1961), in central Europe
by Pouzar (1985 b) and Petrini and Müller (1986), while Granmo et al.
(1999) reported a fairly large number of collections from northern Europe (Denmark,
Finland, Norway and Sweden), and Dennis (1974) recorded it from U. K. Most of
these records are on Salix sp., but Granmo et al. (1999) reported N.
effusa on other hosts (Betula, Populus and Quercus) and interestingly
on Polypores ( Phellinus). Our collection is likely to be the first published
one from France.
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