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Hypoxylon terricola Miller.
Stromata superficial on coniferous needles litter, effused-pulvinate,
2-15 mm broad x 0.8-1.3 mm thick, soft leathery; surface silver grey when immature,
greyish brown to blackish brown when mature, with conspicuous perithecial
mounds; internal tissue soft, whitish, delimited by a black outer and basal layer
30-40 µm thick; margin abrupt.
Perithecia subglobose, 0.4-0.5 mm diam.
Ostioles papillate, obtuse, black.
Asci cylindrical, short-stipitate, the spore-bearing parts 100-110
µm long x 8-10 µm broad, the stipes 35-55 µm long, with apical apparatus amyloid,
cuboid to slightly broader than high, 2.5-3 µm high x 3-3.5 µm broad.
Ascospores
11.5-16.5 x 5.5-7 µm, dark brown, ellipsoid-inequilateral with narrowly to broadly
rounded ends, with a conspicuous germ slit spore-length on the less convex side
and a gelatinous sheath up to 1.3 µm thick visible on the less convex side of
young ascospores (in China ink).
Specimen examined: FRANCE: Hérault (34): Bédarieux,
Forêt des Ecrivains Combattants, 1000 m elev., 16 Oct. 1976, FC-5285, on needles
litter under Cedrus atlantica.
Notes: Hypoxylon terricola is definetely not a Hypoxylon
as defined by Ju and Rogers (1996), but has not been included in Nemania
by Ju and Rogers (2002) like most of taxa previously classified as Hypoxylon
section Papillata subsection Primo-cinerea by Petrini and Müller
(1986).
Despite its apparent relationship with Nemania, it has not been included
in this genus by Ju and Rogers (2002) basing on its soft fleshy stromata and
its ascospores with a gelatinous sheath. Petrini and Müller (1986) cultured
it and assigned its anamorph to Nodulisporium, an anomalous feature in
Nemania, while Ju and Rogers (2002) assumed it is referable to Geniculosporium.
In the meantime it is accomodated in a suitable genus, we choose to provisionally
present H. terricola along with other Nemania taxa.
While it has been regularly collected in southern France under Cedrus
atlantica (Candoussau, 1977), H. terricola is only known from U.
S. A. from the type collection on burnt ground (Miller, 1961), and remains a
very rarely reported fungus. Interestingly, all French collections indicate
that mature specimens occur in late autumn and winter, between 800-1000
m elev. (Candoussau, 1977).
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