Nemania aenea var. macrospora

              

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PL971007-04

PL971007-04

JF02206

JF98125

JF02206

PL971007-04

JF98185

JF02206

JF98185

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 m long, the stipes averaging 80 m long, with apical apparatus amyloid, cuboid to cylindrical, 2-3.5 m high x 2-2.5 m broad.

Ascospores 13-18 x 5-6.8 m, 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 m long on the less convex side.

Specimens examined: FRANCE: Arige(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): Fort de Quncan, 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.