Nemania serpens (Pers. Fr.) S. F. Gray var. colliculosa
(Schwein.: Fr.) Y.-M. Ju & J. D. Rogers.
Stromata superficial, irregularly effused to elongate, 3-42 mm long
x 2-15 mm broad x 0.5-0.9 mm thick, weakly carbonaceous; surface dull black,
rarely copper brown to dark brown, plane or with inconspicuous perithecial mounds, when immature
coated with a fugacious greyish brown hyphal layer; interperithecial tissue whitish to
black, basal tissue whitish, inconspicuous or up to 0.4 mm thick; margin abrupt.
Perithecia subglobose to depressed-spherical, 0.4-0.5 (-0.6) mm diam.
Ostioles minutely papillate, black.
Asci cylindrical, long-stipitate, the spore-bearing parts 60-80 µm
long x 6-8 µm broad, the stipes 50-70 µm long, with apical apparatus amyloid,
cylindrical to slightly urn-shaped, 2.7-3.5 µm high x 2-2.5 µm broad.
10-12 (13.5) x 4.7-5.5 µm, pale to medium brown, ellipsoid-inequilateral with
broadly rounded ends, at times suballantoid, with a short inconspicuous germ
slit on the less convex side.
Specimens examined: FRANCE: Ariège (09): La Bastide
de Sérou, Antuzan, 19 Oct. 2001, JF-01224, on Quercus robur; Rimont,
Las Muros, ruisseau de Peyrau, 17 Oct. 2001, JF-01223, on Quercus robur;
Rimont, Las Muros, 22 Oct. 2001, JF-01231, on Quercus robur; Salau, banks
of Salat, 850 m. elev., 09 Jul. 2000, JF-00116, on Robinia pseudoacacia;
Vernajoul, Pont Fagé, ruisseau de Vernajoul, 31 Aug. 2002, JF-02149, on Sambucus
nigra. Haute Garonne (31): Lestelle de St. Martory, Mauris,
11 Aug. 2002, JF-02142, on Ulmus sp. Loir et Cher (41):
Molineuf, Forêt Domaniale de Blois, 09 Feb. 2001, L 01367 A, leg. P. Leroy, on
Notes: Nemania serpens var. colliculosa differs from
the typical variety in less carbonaceous stromata with inconspicuous perithecial
mounds and smaller perithecia. Microscopically, its asci differ in that apical
apparatus is amyloid. Its field identification remains very difficult and needs
a confirmation relying on observation of asci in Melzer's reagent. Granmo et
al. (1999) consider it as a distinct species, as N. colliculosa (Schwein.:
Fr.) Granmo. They also describe N. prava Granmo, differing from N
colliculosa in perithecial size and colour of ascospore masses, but this
distinction was refuted by Ju & Rogers (2002).
Nemania serpens var. colliculosa is reported from France for
the first time. In our experience, N. serpens var. colliculosa is not
uncommon but probably confused in the field with N. serpens. It is mostly found on Quercus wood, but also occasionally recorded
on Carpinus betulus, Corylus avellana, Robinia pseudoacacia,
Sambucus nigra, Tilia platyphyllos and Ulmus sp.