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Nemania aenea (Nitschke) Pouzar
Stromata superficial, effused, irregularly ellipsoid
to elongate, frequently coalescent, 10-45 mm long x 2-8 mm broad x 0.5-0.6 mm
thick, weakly carbonaceous, at times uniperitheciate at margin; surface blackish brown to dull black, with usually
conspicuous globose perithecial mounds, when immature surrounded and coated with
a white to beige fugacious hyphal layer bearing the anamorph; margin abrupt.
Perithecia
spherical to obovoid, 0.3-0.5 mm diam x 0.4-0.5 mm high.
Ostioles
papillate, conical, black, darker than the stromatal surface.
Asci cylindrical, usually long-stipitate,
the spore-bearing parts averaging 90 µm long x 7.5 µm broad, the stipes averaging
60 µm long, with apical apparatus amyloid, cylindrical to urn-shaped, 3-4 µm high x 2.5-2.8
µm broad.
Ascospores 14-17.5 x 6-7 µm, light to medium brown, ellipsoid-inequilateral
with broadly rounded ends, with a conspicuous short germ slit 7-8 µm long on the less
convex side.
Specimens examined: FRANCE: Ariège (09):
Vernajoul, Pont Fagé, ruisseau de Vernajoul, 31 Aug. 2001, JF-01180, on Alnus
glutinosa; same location, 01 Jul. 2002, JF-02116, on Ulmus sp. Morbihan
(56): Forêt de Quénécan, Etang du Fourneau, 23 Oct. 2002, JF-02202, on Fagus
sylvatica.
Notes: Our collections agree well
with the descriptions of N. aenea given by Pouzar (1985 b) and Granmo
et al.(1999).
Macroscopically, N. aenea
is much like N. serpens, with which it is easily confused. It will
be readily distinguished microscopically from N. serpens in having an
amyloid apical apparatus and larger ascospores with a conspicuous short germ slit.
Other Nemania taxa with similar ascospore size range are N. aenea var. aureolutea,
N. aenea var. macrospora and N. chestersii, the both former
have ascospores with an obscure
germ slit, the latter has longitudinally striate ascospores.
According to Pouzar (1985b), N. aenea
was so far known from Central Europe (Germany and Czechoslovakia), while Granmo
et al. (1999) reported it from Denmark and U. K. Our records
in Brittany and Central Pyrénées are likely to be new for France. In Ariège,
N. aenea is so far known from only one location, where it is surprisingly
fairly abundant, while it is absent from all other collecting sites where a
systematic checking of all Nemania specimens has been carried out. Therefore,
N. aenea can be considered as a rare species, locally abundant in
favorable situations.
Like Pouzar (1985 b) and Granmo et al.
(1999), we found it mostly on
rotten wood of Alnus glutinosa, apparently driftwood lying on the banks of a stream,
but we also recorded it on Fagus sylvatica, Populus tremula, Robinia pseudoacacia
and Ulmus sp.
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