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Nemania aenea (Nitschke) Pouzar var. macrospora
(Miller) Ju & Rogers.
Stromata superficial, irregularly effused, undulate, 3-22 mm long
x 2-8 mm broad x 1-2.3 mm thick,
weakly carbonaceous; surface lead grey to brownish or blackish grey, with inconspicuous perithecial mounds, when immature
surrounded and coated with a whitish to cream hyphal tissue; margin effused;
the tissue beneath the perithecial layer conspicuous, 0.2-1.2 mm thick, whitish, soft, of
fungal hyphae.
Perithecia subglobose, 0.5-0.8 mm diam.
Ostioles
minutely papillate, black, darker than the stromatal surface.
Asci cylindrical, long stipitate, the spore-bearing parts 72-85 µm
long, the stipes averaging 80 µm long, with apical apparatus amyloid, cuboid
to cylindrical,
2-3.5 µm high x 2-2.5 µm broad.
Ascospores 13-18 x 5-6.8 µm, pale brown,
ellipsoid-inequilateral with usually broadly rounded ends, frequently with one
end pinched or beaked, with a short, fairly conspicuous germ slit 3.5-4 µm long on the less
convex side.
Specimens examined: FRANCE: Ariège(09): Rimont, Las Muros, 09 Nov.
1998, JF-98185, on Fraxinus excelsior(identified by Prof. J. D. Rogers). Aude (11): Bareigne,
Garde Bois, lac de la Ganguise, 15 Feb. 2003, JF-03030, on bark of Quercus
ilex. Loire Atlantique(44): Nantes,
Parc des expositions, banks of Erdre, 07 Oct. 1997, Leroy 971007-04, leg B.
Duhem et P. Leroy, on Alnus glutinosa. Morbihan(56): Forêt de Quénécan,
Etang du Fourneau, 23 Oct. 2002, JF-02206, leg. C. Lechat, on Quercus sp.
Notes: Nemania aenea var. macrospora is distinguished
from the typical variety in having ascospores with a less conspicuous germ slit
and dark grey stromata with inconspicuous perithecial mounds and larger
perithecia. It differs
from N. aenea var. aureolutea in having asci with an apical apparatus
blueing in Melzer's reagent and longer stipes. In addition, a conspicuous
white soft tissue is present under the perithecia even in mature stromata,
and this feature is distinctive among other Nemania taxa examined during
this study (also see N. sp. Leroy-820725-01 and N. sp. Vivant). Ascospores show a high
range of variation in shape and dimensions, and, depending upon the collection
examined, "beaked" ascospores are fairly frequent to absent.
Nemania aenea var. macrospora is known from Europe [Czech
Republic (Pouzar, 1985b)] and North America (Miller, 1961). These seem
to be the first published records from France of this species which is apparently rare,
or overlooked due to its small-sized,
sparse and inconspicuous stromata.
Nemania aenea var. macrospora grows on rotten decorticated
wood or on bark as well, and lacks host-specificity.
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