naturebriefs
9:24in productionCh. 1 · Name and lineage/ 9:24 · ceiling 15 min
Fungi

Auricularia auricula-judae

It is not a food, not a remedy, not a keystone—just an ear-shaped truth, fixed to elder, named after Judas, and finally sorted by DNA.

Auricularia auricula-judae is a European wood-decaying fungus with brown, gelatinous, ear-shaped fruit bodies that grow year-round on elder and other broadleaf trees. It was first described by Linnaeus in 1753 and renamed by Bulliard in 1789. Molecular research later restricted the name to the European lineage. Its common names derive from folklore linking it to Judas Iscariot’s suicide on an elder tree. It was used in 19th-century folk medicine for sore throats, sore eyes, jaundice, and as an astringent. It is edible but not widely consumed.

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Chapters & takeaways4
  1. 0:57
    Name and lineage

    Linnaeus named it in 1753; Bulliard renamed it in 1789; molecular work later confined the name to Europe.

  2. 2:49
    Form and habitat

    Brown, gelatinous, ear-shaped fruit bodies grow year-round on elder and other broadleaf wood in Europe.

  3. 4:22
    Folklore and folk use

    Its name links to Judas’s suicide on an elder tree; it was used in 19th-century folk medicine for sore throats, eyes, and jaundice.

  4. 5:46
    Edibility without appeal

    It is edible—but not widely consumed.

Worth your time?

Yes. See the whole thing.

3.5/ 5
What works
  • reliably fruits on elder across Europe all year
  • has distinct morphology: brown, gelatinous, ear-like
  • has precise taxonomic delimitation via molecular evidence
What does not
  • establish ecological dominance
  • feature in modern clinical medicine
  • support widespread culinary use
  • show conspicuous seasonal abundance
See it if
  • fungal foragers
  • folklore-aware naturalists
  • taxonomists verifying European specimens
Skip it if
  • chefs seeking umami-rich ingredients
  • conservation practitioners tracking population trends
  • field biologists needing indicator species with documented ecological impact
The written brief1 min read

What the species is and where it came from

Auricularia auricula-judae is a European wood-decaying fungus in the order Auriculariales. It was first described by Linnaeus in 1753 as Tremella auricula and renamed by Bulliard in 1789.

How it works, in terms someone would actually use

It grows year-round on broadleaf wood, especially elder, in Europe. Its fruit bodies are brown, gelatinous, and ear-shaped.

What it gets right

It reliably fruits on elder across Europe all year. Its morphology is distinct: brown, gelatinous, ear-like. Its taxonomy is now precisely delimited by molecular evidence.

What it does not

It does not establish dense mycelial networks visible to the naked eye. It does not fruit prolifically on conifers. It does not feature in modern clinical medicine. It is not widely consumed.

What it changed

It clarified species boundaries: molecular research restricted the name Auricularia auricula-judae to the European lineage, separating it from Asian and American lookalikes.

Who it is for, and who it is not

It is for fungal foragers, folklore-aware naturalists, and taxonomists verifying European specimens. It is not for chefs seeking umami-rich ingredients, conservation practitioners tracking population trends, or field biologists needing indicator species with documented ecological impact.

Is it worth your time

Yes—if you walk in European broadleaf woods and want to spot a fungus with folklore, medicinal history, and taxonomic clarity. No—if you seek culinary use, ecological dominance, or conspicuous presence.

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9:41
Geastrum triplexGeastrum triplex is the largest earthstar fungus. It grows saprobically in hardwood forest detritus and leaf litter across Eurasia, Australasia and the Americas. Its immature fruit bodies are spherical and buried. Maturation involves exoperidial splitting into 4–8 rigid rays that lift the spore sac, exposing a gleba that transitions from white/firm to brown/powdery. A layer of the exoperidium often splits around the spore sac’s perimeter, forming a collar or saucer. The peristome is a small pointed beak atop the spore sac with a hole for spore release. It has documented use in traditional medicine (Blackfoot, Cherokee, Chinese) and contains bioactive sterols and fatty acids—but it is not considered edible due to toughness.
8:34
Calvatia giganteaCalvatia gigantea is a temperate-zone puffball mushroom found in meadows, fields and deciduous forests during late summer and autumn. It is edible only when young and solid white inside. Its taxonomy shifted from Lycoperdon and Langermannia to Calvatia as mycologists abandoned the polyphyletic 'gasteromycetes' grouping. It produces trillions of spores internally and yields a white spore print when immature. It is used traditionally as a styptic and is protected in parts of Poland and of conservation concern in Norway.
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Armillaria melleaArmillaria mellea is an edible, bioluminescent, pathogenic fungus that causes Armillaria root rot in hundreds of woody species — especially hardwoods — via black rhizomorphs in cool, moist temperate soils. Its mycelium glows during active growth due to inhibited hispidin synthesis. It shows no visible signs until infected trees display crown dieback, discoloured foliage and death.
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