On fallen twigs or moss-covered trunks of
deciduous trees, or on fallen leaves of e. g. Salix and
stems of different herbs, such as Filipendula ulmaria. Also found on fallen
hazel nuts. Early summer to early winter. There are not many records in The
Norwegian Mycological Database, but it has probably been overlooked because of the small size.
Pileus up to 5 mm
across, hemispherical, conical, becoming more or less parabolical
with age, translucent-striate, shallowly sulcate, white-furfuraceous
to floccose, glabrescent, white or grey. Lamellae
7 - 13, not always reaching the stipe, ascending, narrowly
adnate or attached to a pseudocollarium, the edge convex,
white. Stipe up to 30 mm long,
filiform, straight to flexuous, equal, greyish-hyaline,
puberulous, glabrescent with age, but often hirsute below,
the base somewhat bulbous with a small, hirsute, white,
basal disc. Odour none.
Basidia
14-18 x 7-9 µm, clavate or obpyriform, 2- spored, clamped.
Spores
8.2-9.7 x 5.0-6.1 µm, pip-shaped, smooth, amyloid.
Cheilocystidia
11-32 x 7-18 µm, clamped, clavate or obpyriform to fusiform,
mostly with a slender, straight to curved, simple or occasionally
furcate neck up to 20 µm long; clamped, smooth or
covered with warts or cylindrical excrescences 0.5-1.5 x
0.5 µm. Lamellar trama dextrinoid. Hyphae
of the pileipellis smooth to verrucose,
clamped, with terminal
cells globose to obpyriform, densely covered
with warts. Caulocystidia
20-110 x 6-7 µm, lageniform to cylindrical, smooth.
Basal disc cystidia
similar to the caulocystidia but typically shorter, often
in chains of 2-4 cells, terminal cells 22-60 x 5-12 µm,
cylindrical, clavate, lageniform, obtuse to subacute, smooth
or rarely with a few coarse, apical excrescences. Clamps abundant.
Mycena adscendens may occasionally
grow on hazel nuts (Maas Geesteranus 1991b). Two other
species have been reported growing on hazel nuts: M.
discopus (Lév.) Quél. and M.
nucicola Huijsm. M. discopus
is a somewhat dubious species and awaits further description.
Desjardin (1995: 79) excluded it as a nomen dubium.
Huijsman (1958) described the cheilocystidia of M.
nucicola as clavate, lacking an apical
rostrum and Maas Geesteranus (1991b) did not report otherwise.
Desjardin (1995) and Robich (2003) showed, however, that
many of the cheilocystidia near the pileus margin have a
single apical projection. A Norwegian collection
showed long, flexuous rostrae as in M. adscendens.
M. nucicola can according to Desjardin (1995) be
separated from M. adscendens on account of the
4-spored basidia, somewhat narrower spores and presence
of acanthocysts on the basal disc. The situation is, however,
somewhat more complicated.
M. adscendens is supposed to have
the following differentiating features:
1. 2-spored basidia
2. clamp connections common in all tissues
3. spores (4.8-)5-6(-6.4) µm broad
4. caulocystidia lanceolate, smooth
5. basal disc cystidia variously shaped, shorter than the
caulocystidia, smooth or rarely with a few apical excrescences,
often in chains.
M. nucicola is supposed to have the
following features:
1. 4-spored basidia
2. clamp connections rare on tramal hyphae (absent elsewhere?)
3. spores 4.2-5 µm broad
4. caulocystidia lanceolate with a broadened base, smooth
5. basal disc cystidia of two kinds: a) acanthocysts and
b) elements similar to the caulocystidia, not in chains |
 |
The differences are rather marginal, although
perhaps distinct enough to support a division into two species.
One problem is connected to M. adscendens
var. carpophila (J.E. Lange) Desjardin, which seems
to be very unsufficiently known. The type does not exist.
Important features of this variety are:
1. 4-spored basidia
2. narrower spores?
3. lacking acanthocysts?
4. fruiting on fallen pericarps of Fagus
5. microscopy otherwise as var. adscendens
Lange reported the species as having 4-spored
basidia, narrower basidiospores, and fruits on Fagus
pericarps, but he did not report on cheilocystidia shape
nor caulocystidia, and he certainly was not aware of microscopic
features of the basal disc. Until new material can be found
it is impossible to tell anything certain about this variety,
and it may as well be conspecific with M. nucicola.
Another problem is that Maas Geesteranus (1991
and1991b) reported 4-spored M. adscendens growing
on Corylus fruits. As far as I can understand,
the only remaining difference between 4-spored M. adscendens
and M. nucicola would be the cystidia of the basal
disc. Another possible difference is the occurrence of clamp
connections. In M. adscendens clamp connections
are abundant, while they seem to be very rare in M.
nucicola.
Van den Berg et al. (2000) described the new species Mycena cecidiophila A.P. Berg, Berg-Block, Noordel. & Uljé, that was found growing on old knopper galls on the cups of Quercus robur. It differs from Mycena adscendens in having a consistently brownish centre of the pileus and a conspicuously fimbriate margin. In addition it is characterized by the absence of pleuro- and cheilocystidia and a negative Melzer-reaction on the lamella trama. The authors also proposed the new section Cecidiophilae to accomodate the new species.
Mycena sect.
Sacchariferae Kühner ex Singer comprises
six species in Europe.
Further images on the Internet:
MykoWeb
Société
Mycologique de Strasbourg
Sociedad Micológica Errotari
kulakbiocampus/paddestoelen
http://home.wanadoo.nl/abiemans/e_myc_adsc.html
http://public.fotki.com/mycophiles/mushrooms/dscn0217.html
http://www.treknature.com/images/photos/286/micena-01.jpg |
