What You Should Know
Mycena floridula is a member of the Adonideae section (Maas Gesteranus 1988). It is uncertain whether it is conspecific with Mycena adonis (= Atheniella adonis) (Redhead et al. 2012).
This species is only known from Northern and Central Europe, and the collection for the culture was sampled on spruce (Picea abies) litter in the coniferous forest on Vettakollåsen in Southeast Norway.
Mycena floridula Mushroom Identification
5-15 mm across, at first hemispherical, then conical to convex, occasionally somewhat depressed centrally, glabrous, hardly or very shallowly sulcate, translucently striate or not, hygrophanous, when very young bright coral red with the margin somewhat paler, then pink with a whitish margin, fading to straw yellow with a faint pinkish tinge and paler margin.
18-27 reaching the stem, ascending, narrowly to somewhat broader adnate, sometimes decurrent with a very short tooth, becoming intervenose, yellowish-white to pale pink with a paler edge.
30-65 x 1-1.5 mm, hollow, terete, straight, equal, glabrous except for the pruinose apex, white to yellow-white, rarely with a slight tint of the cap but very much paler; the base densely covered with white fibrils.
Odor and Taste
Basidia 24-30 x 5.5-6 μm, clavate, 4-spored. Spores 7-9.5 x 3.5-5 μm, Q 1.5-2.1, Qav 1.9, pip-shaped to almost cylindrical, smooth, non-amyloid. Cheilocystidia 40-53 x 7-11 μm, occurring mixed with basidia, fusiform to lageniform, smooth and simple, more rarely apically furcate. Pleurocystidia similar. Lamellar trama is not vincent in Melzer's reagent. Hyphae of the pileipellis 1.5-4 μm wide, densely covered with variously shaped excrescences, some up to 10 x 5 μm. Hyphae of the cortical layer of the stipe 1.5-3.5 μm wide, smooth, caulocystidia 7-22 x 5-8 μm, clavate, globose, or subglobose. Clamp connections are present in all tissues.
Mycena floridula Taxonomy
This taxon has usually been named as 'Mycena floridula'. It is rather easily identified on account of the pink color of the cap, but it has been suggested that it is merely a color form of M. flavoalba since there seem to be no microscopical characters distinguishing the two taxa. Besides, 'M. floridula' has been reported to fade in colors so much that it is no longer possible to distinguish the species from M. flavoalba. An important piece of information, however, was provided by A. Hausknecht (Maas Geesteranus 1991: 400), who had observed that the faded specimens of 'M. floridula', when placed in his drying apparatus, regained their original color and have stayed red ever since, whereas no color change was observed in the drying specimens of M. flavoalba.
Sometimes it can be difficult to separate M. floridula from M. adonis, although the latter generally is brighter in color. Following Kühner's description, Maas Geesteranus (1990: 165) used the color of the lamellae and the pileus to distinguish between the two taxa. He stated that in M. adonis the lamellae are 'delicately pink, turning whitish to white whereas they are bright pinkish-red to coral red at their bases, pallescent in M. floridula. He also claimed that in M. adonis the pileus has no trace of yellow, nor turning yellowish when fading. In M. floridula the pileus is 'turning bright yellow with age.
Photo 1 - Author: Arne Aronsen/Naturhistorisk museum, Universitetet i Oslo (Creative Commons Attribution-Share Alike 3.0 Unported)