Growing on fallen Corylus fruits.
Pileus 1.5 - 5 mm
across, at first conical, becoming parabolical with age,
translucent-striate when old, shallowly sulcate, furfuraceous
or floccose, becoming puberulous to glabrous, white. Lamellae
11 - 13, not always reaching the stipe, ascending, the edge
convex, narrowly adnate, white. Stipe
up to 30 mm long, filiform, straight to flexuous, equal,
the base somewhat bulbous, entirely pubescent or hairy,
glabrescent, watery greyish, with age more whitish, with
a very small basal disc, which is almost disappearing with
c. 17 x 8 µm, clavate, 4-spored. Spores
(7-) 8.2-8.8 (-10) x (3.8-) 4.5-4.5 (-5.5) µm, pip-shaped,
15-26 x 8-16 µm, clavate, densely covered with evenly
spaced, short excrescences, with or without a shorter or
longer, often flexuous rostrum. Hyphae
of the pileipellis up to 15 µm wide,
densely covered with narrow, short excrescences; the terminal
cells broadly clavate to globose, up to 30 µm wide,
densely covered with short excrescences 0.5-1.5 x 0.5 µm
(acanthocysts) . Hyphae of the cortical layer
of the stipe smooth, covered with globose
to broadly clavate acanthocysts, similar to the terminal
cells of the pileipellis; the
caulocystidia up to 100 µm long,
smooth, thin-walled, lanceolate, acute, with a broadened
base up to 13 µm wide. Hyphae
of the basal disc
terminated by cells of two types: 1) elements similar
to the caulocystidia, up to 50 µm long, clavate or
lanceolate, entirely smooth or 2) elements similar to those
on the pileipellis, 15-40 µm, clavate to subglobose,
densely covered with short excrescences (acanthocysts).
Clamp connections rare on tramal
This taxon has been regarded as a separate species under the name Mycena nucicola Hujsman. Maas Geesteranus (1991b) and Desjardin discussed the differences between M. nucicola and M. tenerrima (see this). Recent ITS sequences of Norwegian and Swedish collections determined as M. tenerrima and M. nucicola indicated, however, that the two taxa belong to the same species (Aronsen & Larsson 2015). Therefore, I treat it M. nucicola as a synonym.
NORWAY, TJØME, Hvasser, Sønstegård 19 Nov. 2006.
Two specimens on fallen fruit of Corylus avellana, leg. A. Aronsen.