Galerina marginata

What You Should Know

Galerina marginata is a very poisonous mushroom that contains the same deadly toxins as the death cap mushroom. It is characterized by its growth on wood, rusty brown spore print, relatively small caps, and a thin ring or ring zone that may disappear. Its cap is brown to tawny and moist when fresh but often fades in age.

This mushroom is widely distributed throughout North America, Europe, Asia, and Australia from summer to fall. It's important to note that while this mushroom is commonly found in wooded areas, it can also appear in urban or suburban environments where there is dead wood or other organic matter.

Other names: Funeral Bell, Deadly Skullcap, Autumn Skullcap, Deadly Galerina, German (Gifthäubling), Netherlands (Bundelmosklokje).

Galerina marginata Mushroom Identification

1. Cap

   The cap ranges from 0.59 to 1.97 inches (1.5 to 5 cm) in diameter, and can occasionally reach up to 3.15 inches (8 cm). It is initially convex but becomes broadly convex or nearly flat, and may be slightly bell-shaped. The cap is sticky when fresh or wet, but otherwise tacky to dry, and changes from honey yellow with an orangish hue to cinnamon to brownish orange. It may fade noticeably as it dries, creating a two-toned appearance, and is bald with a margin that is sometimes adorned with whitish veil remnants when very young, becoming naked and finely lined at maturity.

2. Gills

   The gills are broadly attached to the stem or just beginning to run down. They are close or nearly distant, and short gills are frequent. The gills are initially yellowish, eventually becoming rusty brown or brownish as the spores mature, and do not bruise, but may become spotted in appearance in old age. They are initially covered by a whitish partial veil.

3. Stem

   The stem is 0.79 to 2.76 inches (2 to 7 cm) long and 0.12 to 0.31 inches (3 to 8 mm) thick, more or less equal, and dry. It is bald or flecked with whitish fibrils when fresh and young, and usually features a thin, whitish to rusty brown, collapsed, bracelet-like ring, but sometimes has only a ring zone or no veil remnants at all. The stem is whitish to brownish, turning dark brown to reddish brown from the base up, and has a white basal mycelium.

4. Flesh

   The flesh is insubstantial, yellowish to watery brownish, and unchanging when sliced. It has a non-distinctive odor, or maybe slightly mealy when crushed between your fingers.

5. Chemical Reactions

   KOH turning red to dull red on the cap surface, ammonia is negative on the cap surface, and iron salts are negative on the cap surface. Its spore print is rusty brown.

6. Habitat

   Saprobic on the rotting wood of fallen hardwoods and conifers; causing a stringy white rot; usually growing in clusters, but occasionally growing gregariously or alone; most frequent in spring and fall, but found year-round; widely distributed and common in North America, Europe, Asia, and Australia..

7. Microscopic Features

   Spores 7-11 x 4-6 µm, broadly amygdaliform to subellipsoid, verrucose, reddish brown in KOH, and often with a loosening perispore. Basidia are usually 4-sterigmate, but occasionally 2-sterigmate. Pleurocystidia and cheilocystidia are similar, 40-65 x 5-15 µm, lageniform, with a long neck and a rounded or subclavate apex, smooth, thin-walled, and hyaline in KOH. The pileipellis is an ixocutis, and clamp connections are present.

Galerina marginata Look-Alikes

1. Kuehneromyces mutabilis

   Distinguished by a non-hemispherical, non-hygrophanous, zonally colored cap, and the absence of light bands on the stem - remnants of a spider web.

2. Flammulina velutipes

   Has a black, velvety stem with no skirt although the stem is light tan on younger mushrooms.

Galerina marginata Toxicity

Galerina marginata is a type of mushroom that contains a toxin called amatoxin. This toxin is responsible for over 90% of fatal mushroom poisonings in humans. Amatoxins stop the enzyme RNA polymerase II from copying DNA into messenger RNA, which leads to liver and kidney failure. Symptoms of poisoning include severe abdominal pain, vomiting, and diarrhea, which can last for several hours. The mushroom can be deadly and may cause coma, gastrointestinal bleeding, kidney failure, or death within seven days of consumption.

It also contains α-amanitin and γ-amanitin, two types of amatoxins. The amount of amatoxins can vary greatly between different specimens of the mushroom. Ingesting just 10 Galerina marginata fruit bodies containing amanitins could poison a child weighing approximately 44 pounds (20 kilograms).

The toxicity of certain Galerina species has been known for a century. Poisonings have been caused by G. autumnalis, G. venenata, and G. marginata. Mistaking them for the hallucinogenic Psilocybe stuntzii has also caused poisonings.

Galerina marginata Taxonomy and Etymology

Galerina marginata used to be considered five different species, but DNA analysis showed that they were all the same species. The oldest name for the species is Agaricus marginatus. Another species called Galerina pseudomycenopsis is similar but is considered a different species because of differences in ecology, fruit body color, and spore size. Galerina marginata is part of Galerina section Naucoriopsis, which includes small brown-spored mushrooms with thin-walled pleurocystidia that are not rounded at the top. G. marginata is in stirps Marginata and is characterized by its growth on wood, rusty brown spore print, relatively small caps, and a thin ring or ring zone that may disappear. Its cap is brown to tawny and moist when fresh but often fades in age.

The specific epithet marginata is derived from the Latin word for "margin" or "edge", while autumnalis means "of the autumn".

Galerina marginata Look-Alikes

• Agaricus autumnalis Peck 1872

• Agaricus caudicinus var. denudatus Pers. 1801

• Agaricus marginatus Batsch 1789

• Agaricus unicolor Vahl 1792

• Galera marginata (Batsch) P. Kumm. 1871

• Galerina autumnalis (Peck) A.H. Sm. & Singer 1964

• Galerina oregonensis A.H.Sm. 1964

• Galerina unicolor (Vahl) Singer 1936

• Galerina venenata (Vahl) Singer 1953

• Galerula marginata (Batsch) Kühner 1934

• Galerula unicolor (Vahl) Kühner 1934

• Gymnopilus autumnalis (Peck) Murrill 1917

• Naematoloma marginatum (Pers.) Courtec. 1986

• Naucoria autumnalis (Peck) Sacc. 1887

• Pholiota discolor Peck 1873

• Pholiota marginata (Batsch) Quél. 1872

• Pholiota unicolor (Vahl) Gillet 1874

• Psilocybe marginata (Pers.) Noordel. 1995

Sources:

Photo 1 - Author: Walt Sturgeon (Creative Commons Attribution-Share Alike 3.0 Unported)

Photo 2 - Author: Strobilomyces (Creative Commons Attribution-Share Alike 3.0 Unported)

Photo 3 - Author: Sarah Culliton (Creative Commons Attribution 4.0 International)

Photo 4 - Author: Strobilomyces (Creative Commons Attribution-Share Alike 3.0 Unported)

Photo 5 - Author: Strobilomyces (Creative Commons Attribution-Share Alike 3.0 Unported)