How to tell Split fibrecap from White fibrecap
How they differ, how to recognize them and which is more dangerous — a mushroom comparison
Warning: Split fibrecap(Pseudosperma rimosum)
POISONOUS
Eating it causes poisoning. Do not pick it unless you have identified it with certainty.
Toxin: muscarine (high concentration — up to 0.2% of dry weight, 100-200 times more than in the fly agaric). Symptoms start 15-90 min after the meal (fast). The classic "muscarinic syndrome" (PSL — "perspiration, salivation, lacrimation"): profuse salivation, heavy sweating, watering eyes, runny nose, constricted pupils (miosis), bronchospasm, bradycardia, low blood pressure, intestinal cramps, diarrhea, nausea, vomiting. Lasts 4-12 hours. In severe cases — collapse, pulmonary edema, risk of cardiac arrest. The antidote is atropine, which blocks muscarine at the muscarinic receptors. Treated only in a hospital — self-treatment with atropine is dangerous. If you suspect poisoning, call 112 or your local emergency number immediately and keep the mushroom leftovers and vomit. The prognosis is good with timely treatment.
If you suspect poisoning, call an ambulance immediately: 112 (the European emergency number) or your local emergency number
Warning: White fibrecap(Inocybe geophylla)
POISONOUS
Eating it causes poisoning. Do not pick it unless you have identified it with certainty.
If you suspect poisoning, call an ambulance immediately: 112 (the European emergency number) or your local emergency number
The short answer
Split fibrecap and White fibrecap look alike, so they're easy to mix up — but Split fibrecap is poisonous, while White fibrecap is poisonous. Compare the color and shape of the cap, the stem, the flesh and the smell, as well as the season and habitat — details in the table below. If you have even the slightest doubt, leave the mushroom be.
Split fibrecap
Pseudosperma rimosum
White fibrecap
Inocybe geophylla
📊 Comparing characteristics
⚠ Highlighted rows are the key differences between the edible and the dangerous mushroom
| Characteristic | Split fibrecap | White fibrecap |
|---|---|---|
| Edibility class | Split fibrecap Poisonous | White fibrecap Poisonous |
| ⚠ Season | Split fibrecap SummerAutumn | White fibrecap — |
| ⚠ Use | Split fibrecap Not eaten | White fibrecap — |
| ⚠ Size | Split fibrecap Small (up to 5 cm) | White fibrecap — |
| ⚠ Cap color | Split fibrecap YellowOrangeBrown | White fibrecap — |
| ⚠ Cap shape | Split fibrecap Conical | White fibrecap — |
| ⚠ Cap surface | Split fibrecap Cracked | White fibrecap — |
| ⚠ Taste | Split fibrecap Mild | White fibrecap — |
| ⚠ Smell | Split fibrecap Chemical | White fibrecap — |
| ⚠ Flesh color change | Split fibrecap No change | White fibrecap — |
| ⚠ Hymenophore | Split fibrecap Gilled | White fibrecap — |
| ⚠ Stem | Split fibrecap Central | White fibrecap — |
| ⚠ Ring (veil) | Split fibrecap No ring | White fibrecap — |
| ⚠ Volva | Split fibrecap No volva | White fibrecap — |
| ⚠ Substrate | Split fibrecap Soil | White fibrecap — |
| Nutrition type | Split fibrecap Mycorrhizal | White fibrecap Mycorrhizal |
| ⚠ Partner trees | Split fibrecap OakBeechHornbeamBirchHazel | White fibrecap — |
📅 Seasonality
Split fibrecap
Fruiting season
June – October
White fibrecap
🔬 Morphology
Cap
Split fibrecap
Cap 2-7 cm across; in young mushrooms conical or bell-shaped with a pointed knob, later it opens out, but the knob stays. Color yellowish-ochre, straw-yellow, light brown in old mushrooms. The surface has a distinctive radially fibrous pattern, and when mature — deep radial cracks from the center to the edge (hence the species name rimosum — "cracked"). The margin is often split and upturned.
White fibrecap
No data
Hymenophore
Split fibrecap
Gilled hymenophore. Gills fairly crowded, notched where they meet the stem. In young mushrooms they are whitish-gray, turning olive-brown or tobacco-colored with age. Spore print tobacco-brown or tobacco-colored — typical of the whole genus Inocybe.
White fibrecap
No data
Stem
Split fibrecap
Stem 3-8 cm tall, 0.4-1 cm thick, cylindrical, even or slightly thickened toward the base. Whitish to yellowish, paler at the top. Surface lengthwise fibrous, no ring. Flesh of the stem firm, hollow in old mushrooms.
White fibrecap
No data
Flesh
Split fibrecap
Flesh thin, whitish to yellowish, does not change color when cut.
White fibrecap
No data
Smell
Split fibrecap
Distinctly spermatic or stale and musty — typical of the whole genus Inocybe. This is an important diagnostic sign: if an unknown brownish mushroom has this unpleasant smell, throw it away without hesitation. Some sources describe the smell as "stale flour". The taste is mild or slightly bitter — do NOT rely on taste.
White fibrecap
No data
📍 Habitats
Split fibrecap
White fibrecap
No data
👀 Similar mushrooms — don't mix them up!
❓ Frequently asked questions
Can Split fibrecap and White fibrecap be mixed up?
How to tell Split fibrecap from White fibrecap?
Which is more dangerous — Split fibrecap or White fibrecap?
Is White fibrecap edible?
When do Split fibrecap and White fibrecap grow?
Sources
- [1]Вікіпедія (українська)
- [2]Атлас грибів України, Зеров Д.К. (1979)
- [3]MycoBank Database
- [4]Index Fungorum
- [5]GBIF
- [6]iNaturalist Ukraine