LBM - Little Brown Mushrooms

LBM is a famous acronym to describe the mushrooms that most laypeople never bother to learn... too small and too drab to be noteworthy (and therefore very difficult to tell apart). Although the phrase LBM refers to many more mushrooms than are found on this page, I am extending the definition of brown to also refer to the spore colour. These are the drabbest of the drab, where even on a microscopic level, the spores are not an interesting colour. (To be fair, Bolbitius has some non-brown mushrooms). Most are saprophytic, but Alnicola is mycorrhizal.

Key to LBMs: (hygrophanous and dry capped, unless otherwise stated).

• Phaeomarasmius/Flammulaster - scaly cap and often stem too on wood/ground. Not hygrophanous.
• Bolbitius - yellow or lilac colours, in grass, straw or dung. Viscid.
• Albogymnopilus - (below) a rare white LBM without a conical cap and with rusty gills. Not hygrophanous.
• Tubaria - try here first for adnate to decurrent gills or strongly hygrophanous caps. Possibly brick red.
• Melanotus - stem often eccentric, sometimes growing on fabric, otherwise on wood. Not hygrophanous.
• Simocybe - overall pruinose (powdery) look and white mycelium at the base of the stem, on wood.
• Conocybe - often sharply cone headed LBMs, possibly with a ring, in grass or on rotting wood.
• Galerina - hemispherical or broadly conical caps growing on moss or wood, possibly viscid and with a ring or ring zone.
• Alnicola - try here first for flat caps, growing on the ground. Not hygrophanous.

Albogymnopilus - white with rusty gills. The true position of this rare mushroom is not known, and may deserve a genus of its own.

Albogymnopilus nana

Melanotus - sometimes with an off-centre stem so you will also find it on the oyster mushroom page. Pale to dark brown, found on wood or sometimes on carpets and fabric! It may have regular brown or dark purple-brown spores. It is related to (and probably actually is) Deconica (Psilocybe) in the Strophariaceae family, although it does not really resemble it from a human point of view. Dryer cap than Pholiota. Something close to adnate gills, but attachment varies. Tiny mushrooms are hard to get a spore print from, so you may even look for it on the white spored marasmioid page. Very small (<2.5cm). Dry capped and not hygrophanous.

Deconica (Melanotus) horizontalis (textilis) - pale to dark brown, sometimes furry cap and stem. Purple-brown spores. <2cm.

D. (M.) phillipsii - paler with pale brown spores, not furry, found in the wild on dead grasses and sedges. <1cm.

Specimens I found today on an old kitchen scrubbie I left in the wash basin.

Phaeomarasmius/Flammulaster - scaly LBMs, with granular to floccose scales all over the cap and stem. The two genera intergrade and either need to split into even more obscure, tiny genera, or (hopefully) all be called by the older name Phaeomarasmius.

Phaeomarasmius 'erinaceus' - Dark brown, dry, very floccose scaly cap, on hardwood. Somewhat adnate gills. <1.5cm. Scalier than Melanotus. Dryer cap than Pholiota. Closely related to Tubaria.

Phaeomarasmius proximans - recently discovered in WA, with subtler dark scales on a yellow ground cap colour.

Flammulaster carpophilus grp - also scaly (but more granulose than Phaeomarasmius). Somewhat adnate gills. <1.5cm. Pale brown.

F. muricatus grp - not quite as pale brown.

Simocybe - on wood, with an overall pruinose look and white mycelium visible at the base of the stem and white gill edges, but not distinctive and hard to recognize. (Smaller and not viscid like Pholiota, and a different look and feel than Galerina or Tubaria). Cap usually hygrophanous. Gills usually adnexed but variably attached. Very similar to Melanotus, which almost always has a shorter stem and colder, darker brown spores. This genus is related to Crepidotus, and has never been studied in the west, so take these reports and rumours of what species are here with a grain of salt.

S. sumptuosa - the largest species, sometimes >2.5cm.

S. centunculus - cap perhaps more reddish than S. sumptuosa.

S. haustellaris/rubi - "oyster" like, stem may be off centre or missing like Melanotus.

Tubaria - Well, this is it, the quintessential LBM that David Arora calls the boringest of the boring. I disagree, however, as I always try to find something interesting to say about every mushroom and I generally subscribe to the "if you can't say something nice about something..." theory. In this case, Tubarias are strongly hygrophanous. The colour change as they dry out is quite dramatic (see first photo) and can start to happen in a matter of minutes. Two of them can be blood red. Traditionally recognized by having slightly decurrent gills, although that's not foolproof. Supposedly dry capped and striate at least when moist. Related to Phaeomarasmius/Flammulaster.

T. furfuracea/hiemalis - common anywhere at any time, supposedly the two species were split by summer (winter) months on soil (wood) with a strong(weak) white(ocher) veil, but DNA is not bearing out those differences. Usually <2.5cm.

This specimen from that group is not as delicate, with a darker red colour and veil remnants along the cap rim. The two species hybridize, sometimes making the DNA indistinguable from either species. Hmm.

T. 'conspersa' - even smaller stature (<2cm), fibrils all over the cap and stem, not as granular as Flammulaster.

T. 'confragosa' - veil may leave a ring on stem, bigger, up to 5cm, may be somewhat reddish. Usually on wood. Resembles the deadly Galerina and Conocybe.

T. punicea - fleeting veil, on Madrone, brilliant burgundy. Resembles Laccaria. Also up to 5cm.

T. vinicolor - similarly red but not as brilliant, especially in the stem. Found on different trees.

Bolbitiaceae - delicate LBMs found in urban places (grass, manure, rotting debris or wood) with an often viscid, striate cap. Gills may be free but are sometimes adnexed. They are very much like Psathyrella and the inky caps, but with lighter brown spores. The spores have a kind of a rusty tint to them like Cortinarius, but these are usually paler. This gives these mushrooms cinnamon coloured gills in maturity.

This family has a cellular cap cuticle (the top layer of cells inflated and round) like Agrocybe, Psathyrella, Panaeolus and the Inky Caps. (And the Russulaceae, but their entire fruitbody is cellular). This can make the caps susceptible to wrinkling or sparkling in the sun, but it also makes them susceptible to breaking in any direction, not just radially from the cap to the centre. Put a little bit of pressure on the cap by bending it and see if you can get it to easily break like this:

That might indicate a cellular cap cuticle, although any old rotting mushroom is also likely to break easily in any direction.

Bolbitius - usually a viscid, striate capped, yellow or lilac LBM. <4cm.

B. titubans ('vitellinus') - viscid, yellow, striate. The yellow will fade.

B. titubans var. olivaceus (variicolor) - may have olive cap colours mixed with yellow, may look identical.

Sometimes a wrinkled net like pattern develops in the caps of Bolbitius due to the cellular cap cuticles.

B. 'reticulatus' - lilac grey cap even when young, some yellow in stem. Viscid.

Conocybe/Pholiotina s.l. - the "coneheads". Often strongly conical, dry sometimes striate capped, delicate brown or white LBMs, typically hygrophanous. Conocybes have no veil, but Pholiotinas have a veil that leaves a ring on the stem. At least some of those are DEADLY POISONOUS containing the same toxin as the deadly Amanitas. (Remember, rings can fall off, so any LBM could potentially be deadly). Conocybe can be told microscopically by the exaggerated round headed sterile "cystidia" on the gill edges that look like bowling pins. Pholiotina s.l. does not have them. Usually <2.5cm.

Conocybe semiglobata group ('tenera') - brown cone-head, no veil, long mistakenly called C. tenera. Besides a few common species in this group, we have at least four rarer unrelated lookalikes.

'Pholiotina III' sp. - not only doesn't it have a name yet, but it needs a new genus name too. Usually paler stem than Conocybe semiglobata and no bowling pin cystidia and no veil.

Conocybe aff michiganensis - dark spores almost like Psathyrella, possibly pleated cap.

C. lactea (apala) - whitish at least in age, usually in grass.

C. aurea - gold cone-head, paler stem than C. semiglobata.

'Pholiotina' smithii/cyanopus - weak veil, but no ring. Bottom of stem turns blue, from psilocybin. Needs a different new genus name than the previous one.

Pholiotina rugosa - ring on stem, not as cone-headed. Resembles Galerina and Tubaria. DEADLY!

P. stercoraria/fimicola - ringed Pholiotinas found in dung. P. stercoraria is not very conical, like P. rugosa. P. fimicola may have a darker cap.

Alnicola (Naucoria) - some of our smallest mycorrhizal mushrooms, these, as the Latin translation "alder loving" might suggest, can only be found under hardwoods like alder, or sometimes willow. Dry, non hygrophanous cap, usually fairly flat (unlike Galerina), gills usually adnexed (unlike Tubaria, the two genera with which it is most easily confused). But in practice, very difficult to recognize as there is nothing distinctive about them. Alnicola have warty spores. Usually <2.5cm across. Other Alnicolas under alder can be found in the PNW, but they are little studied. Closely related to Hebeloma.

A. 'melinoides' (Naucoria 'escharioides') - under alder, pale sometimes with paler margin.

A. luteolofibrillosa - lots of white thread-like veil material all over the cap and stem.

A. salicis (Naucoria macrospora) - under willow, darker with even darker umbo.

A. amarescens (geraniolens?) - also under willow, brownish orange cap drying to pale. Odor of geraniums. May be bitter.

Galerina - a confusing unrelated group of LBMs, many of these will need new names as our local Galerina are going to be split into at least 5 different genera, currently nicknamed Galerina, Naucoriopsis, Mycenopsis, Tubariopsis and Sideroides. The Galerina vittiformis group may be the only one on this page to keep the name Galerina. They are found on moss, logs, or mossy logs. The caps are usually dry but occasionally viscid, usually hygrophanous, either having a veil or not maybe leaving a ring on the stem and usually adnexed gills in age but sometimes starting out decurrent like Tubaria. Like Pholiotina (Conocybe), those with a ring may be DEADLY POISONOUS with Amatoxins. Beware all LBMs with a ring, and those without because they may have lost their ring. Most Galerina have warty spores but at least one of the groups has smooth spores.

There are larger species with hemispherical to flat somewhat striate caps, and smaller Mycenoid species with conical, strongly striate caps and pruinose stems (tiny white powdery dots). The latter species are very much like Mycena, as a matter of fact. All usually hygrophanous, most with a pruinose stem apex and often with a dark stem base. In practice, many are almost impossible to tell apart without a microscope and a lot of practice with it.

G. marginata/castaneipes - large and fleshy (for a Galerina) >2.5cm, viscid?, on wood, occasionally ground, veil leaves a ring or not. Cap hemispherical to flat, resembles Kuehneromyces. DEADLY. Farinaceous. Pruinose stem apex. (/Naucoriopsis)

G. badipes - more slender (<2.5cm) on woody debris, rigid stem, with a dark base (like almost every species), ring zone, cap convex to flat, resembles Alnicola.

G. stylifera/sideroides - on wood or buried wood, similar, also larger (up to 5cm), viscid caps. Veil band/none on the stem. Smooth spored group. Not usually pruinose. (/Sideroides)

G. mammillata - similar, perhaps with a more prominent umbo, on wood, dark stem, faintly striate, smooth spored,  <2.5cm, not usually pruinose. (/Sideroides)

G. semilanceata (heterocystis/dimorphocystis) grp - mycenoid, conical cap, striate, pruinose stem. In moss on the ground. Usually >1cm. Mycena but for cinnamon gills and white banding on a stem that does not darken. (/Tubariopsis)

G. clavata - very similar EU species has now been found here.

G. subfiliformis/pumila - similar, smooth spored. (/Mycenopsis)

G. nigripes - mycenoid, but not pruinose like the others, and a dark stem bottom. <1cm. On mossy wood. (/Tubariopsis)

G. vittiformis grp (atkinsoniana) - mycenoid, in moss, much like G. heterocystis but smaller, usually <1cm. Stem does darken. (/Galerina)

I'm having trouble picturing a coffee table picture book on Galerina or Tubaria. However, a mostly all-text copy of Smith's 1964 monograph on is available here.