Galerina is a genus of small brown-spored saprotrophic agarics, with over 300 species found throughout the world, from the far north to remote Macquarie Island in the Southern Ocean. This group is most noted for toxic species which are occasionally confused with hallucinogenic species of Psilocybe.
Taxonomic Definition
The genus Galerina is defined as small mushrooms of myceniod stature, with a
pileipellis that is a cutis, and ornamented spores that are brown in deposit, where the spore ornamentation comes from an extra spore covering.
Features of fruiting bodies
Galerina fruiting bodies are typically small, undistinguished mushrooms with a typical "
little brown mushroom" morphology and a yellow-brown, light brown to cinnamon-brown
spore print. The
pileus is typically
glabrous and often
hygrophanous, and a
cortina-type veil is present in young specimens of roughly half of recognized species, though it sometimes disappears as the mushroom ages in many of these species. Microscopically, they are highly variable as well, though most species have
spores that are ornamented, lack a germ pore, and have a
plage. Many species also have characteristic
tibiiform cystidia. However, there are many exceptions, and many species of
Galerina lack one or more of these microscopic characteristics. Ecologically, all
Galerina are
saprotrophs, growing in habitats like rotting wood or in moss.
Galerina has recently been found to be polyphyletic, consisting of at least three unrelated clades, although not all species were studied and for most currently recognized species is uncertain still in which they belong. Each of these clades corresponds to a subgenus of Galerina, as outlined by Kühner. The great diversity of micromorphology found in Galerina is probably due to the polyphyly of the genus.
The spores of Galerina feature an ornamentation that comes from the outer layer of the spore breaking up on maturity to produce either warts, wrinkles or "ears", flaps of material loosened from where the spore was attached to the basidia. This outer layer of the spore often is not complete, but has a clear patch in many species just above the attachment, this clear patch is called a plage. This plage is not evident in all species, and the spore covering does not always breakup in all species, making it sometimes difficult to correctly determine a mushroom of this genus.
The specific features that define the genus require a microscope to confirm. In the wild it can be difficult to determine a Galerina from a number of similar genera, such as Pholiota, Tubaria, Conocybe, Pholiotina, Agrocybe, Gymnopilus, Phaeogalera and Psilocybe. For the most part, Galerinas will be found associated with moss, and this can separate out the genus in nature fairly well. But this identification is more difficult in the section Naucoriopis, which does not associate with moss, and is a decomposer of wood.
Phaeogalera is genus that was segregated from Galerina by Kühner. Phaeogalera resemble Galerina in their habitat, macroscopic appearance, and spore print color, however, their microscopic characteristics (smooth spores with a distinct germ pore and non-tibiiform cystidia) more closely resemble Psilocybe. A recent study confirms the affinity of Phaeogalera and the non-psilocybin Psilocybe.
Chemistry and toxicology
Many (though not all)
Galerina contain
alpha-amanitin and other
amatoxins.
Galerina steglichii is very rare, bruises blue and contains the hallucinogen
psilocybin.
Identification
Separation from Psilocybe
The extreme toxicity of some
Galerina species means that recognition of
Galerina is of great importance to
mushroom hunters who are seeking hallucinogenic
Psilocybe. Species like
Galerina marginata may bear a superficial resemblance to
Psilocybe cyanescens and other
Psilocybe species.
Galerina can be distinguished from psilocybian
Psilocybe by the following characteristics:
- Spore print color: blackish-brown to lilac-brown in Psilocybe, light brown to rusty brown in Galerina. Spore color can be seen by taking a spore print or by looking for evidence of spore drop on the stipe or on surrounding mushrooms.
- Staining reaction: Psilocybian Psilocybe fruiting bodies stain blue to varying degrees when bruised, while Galerina do not. The strength of this reaction varies with the amount of psilocin present in the tissues of the mushroom. Fruiting bodies with little psilocin will stain weakly if at all, while sporocarps with a high psilocin content will stain strongly blue. Only one rare Galerina has blue-staining tissue, though in some cases the flesh will blacken when handled, and this may be misinterpreted as a bluing reaction.
Although these rules are specific to the separation of Galerina from certain Psilocybe, since mixed patches of Psilocybe and Galerina can occur, it is essential to be sure of the identity of each sporocarp collected.
Galerina also present some risk of confusion with several species of small edible mushrooms, notably Kuehneromyces mutabilis and "candy cap" Lactarius (L. camphoratus, L. fragilis, and L. rubidus).
Notable species
Galerina vittiformis is the
type species of the genus
Galerina. This species is common in beds of damp moss (along with many other species of Galerina). There are a number of variations of this species that have been named over the years: var.
vittiformis f. vittiformis is a 2-spored species; var.
vittiformis f. tetrasporis is a 4-spored form; var.
pachyspora has been collected on
Macquarie Island.
Galerina marginata (also known as autumn skullcap, or deadly galerina) is a poisonous species found throughout the temperate regions of the world, in habitats as diverse as forests and urban parklands, wherever rotting wood is found. DNA studies found that Galerina autumnalis and five other species of Galerina with similar morphologies were, in fact, synonyms of Galerina marginata.
Galerina sulcipes, a lethal species found in Indonesia and responsible for deaths there. One study found it more toxic than Amanita phalloides.
Several Galerina species are listed by the US Forest Service as "species of special concern" in the Northwest Forest Plan. These species are considered indicator species for old growth coniferous forest in the Pacific Northwest: Galerina atkinsonia, Galerina cerina, Galerina heterocystis, Galerina sphagnicola, and Galerina vittiformis.
References
Further reading
- Gulden G. (1980). Alpine Galerinas (Basidiomycetes, Agaricales) with special reference to their occurrence in South Norway at Finse on Hardangervidda. Norwegian Journal of Botany 27: 219–253.
- Gulden G, Hallgrímsson H. (2000). The genera Galerina and Phaeogalera (Basidiomycetes, Agaricales) in Iceland. Acta Botanica Islandica 13: 3–54.
- Gulden G, Vesterholt J. (1999). The genera Galerina Earle and Phaeogalera Kuhner in the Faroe Islands. Nordic Journal of Botany 19: 685–706. (abstract)
- Smith AH, Singer R. (1964). A monograph of the genus Galerina Earle New York: Hafner Publishing Co. 384 p. (Full text available through link)
External links