What You Should Know
Amanita gemmata is a deadly poisonous mushroom of the family Amanitaceae and genus Amanita. The fruit body has a cap that is dull to the golden shade of yellow. The cap surface is sticky when moist, and characterized by white warts, which are easily detached. It is initially convex and flattens out when mature. The flesh is white and does not change color when cut. The gills are white and closely spaced. The stem is pale yellow. The partial veil that covers the young fruit body turns into the ring on the stem at maturity. It can grow either singly, scattered, or in groups. It prefers habitats like coniferous and mixed forests and alongside paths, where it fruits in summer and fall.
It is widespread in Asia, Europe, and North America, where it has been found as far south as Ixtlán de Juárez, Mexico. The species has been reported from the Dominican Republic. In South America, it is known from Chile and Colombia. In Asia, the mushroom has been collected from Iran and China.
It is a toxic mushroom, containing muscarine, also found in many species in the Clitocybe and Inocybe genera, as well as in Amanita muscaria and A. pantherina. It is often confused with various other European species. A. gemmata resembles the false death cap, tawny grisette, and panther cap mushrooms. Its cap is brighter in color than the former and more yellow than the latter two.
Other names: Jonquil Amanita, Gemmed Amanita.
Amanita gemmata Mushroom Identification
3-11 cm; convex to planoconvex or flat; dull yellow, fading to nearly whitish; sticky when fresh; when young covered with white warts that are easily lost as the mushroom matures; bald; the margin often lined by maturity.
Free from the stem; close or nearly distant; whitish; with frequent short-gills.
4-14 cm long; 1-2 cm thick; tapering slightly to the apex; with a small basal bulb; bald or finely hairy; white; with a fragile white ring that is easily lost; with a white volva that typically clings tightly to the bulb and extends to form a free rim on the upper edge of the bulb, but may fragment into soft patches or warts at the top of the bulb.
White; unchanging when sliced.
Mycorrhizal with various hardwoods and conifers; growing alone, scattered, or gregariously; summer, fall, and winter; California and the Pacific Northwest.
Amanita gemmata Look-Alikes
The cap is larger and paler with white or citrine patches. The stem has a distinct stem ring.
Is similar in appearance to A. gemmata but is larger.
A mushroom ranging from Japan to China is a look-alike, but has clamps, unlike A. gemmata. Other differences between the two species include the slightly smaller spores of A. orientigemmata, and differences in the microstructure of the cap warts.
Amanita gemmata Toxicity
This mushroom contains two types of toxins:
Also known as agarin or pantherine is one of the principal psychoactive constituents of Amanita muscaria and related species of mushroom. Muscimol is a potent and selective orthosteric agonist for the GABAA receptors and displays sedative-hypnotic, depressant and hallucinogenic psychoactivity. This colorless or white solid is classified as an isoxazole.
Also referred to as ibotenate, is a chemical compound and psychoactive drug which occurs naturally in Amanita muscaria and related species of mushrooms.
Generally, symptoms of poisoning appear within three hours of ingestion of the mushroom as visual hallucinations, nausea, vomiting, stomach pain, diarrhea, irregular and slow heartbeat and agitation. Severe cases involving coma, convulsions, or death are extremely rare.
Amanita gemmata Taxonomy and Etymology
In 1838 Swedish mycologist Elias Magnus Fries described this species and named it Agaricus gemmatus.
The new name Amanita gemmata was given by Louis-Adolphe Bertillon in 1866.
The specific epithet means gemmed or jewelled.
Amanita gemmata Synonyms
Amanita gemmata (Fr.) Gillet 1874
Amanita junquillea Quél. 1876
Amanitopsis adnata (W.G. Sm.) Sacc. 1887
Amanita muscaria var. gemmata (Fr.) Quél., 1886
Amanitopsis gemmata (Fr.) Sacc., 1887
Amanita adnata (W.G. Sm.) Sacc. 1925
Amanita junquillea var. exannulata J.E. Lange 1935
Amanitaria gemmata (Fr.) E.-J. Gilbert, 1940
Venenarius gemmatus (Fr.) Murrill, 1948
Photo 1 - Author: Scott Darbey from Canada (Creative Commons Attribution 2.0 Generic)
Photo 2 - Author: Tanja Hindemith (Creative Commons Attribution-Share Alike 3.0 Germany)
Photo 3 - Author: Dick Culbert from Gibsons, B.C., Canada (Creative Commons Attribution 2.0 Generic)
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