Taxonomy of Toxins

Tricholoma pessundatum

investiganda

f. cul.

Tricholoma pessundatum investiganda

investiganda: Owed an investigation. The species is on the Needs Investigation table because a question stands on its published record that the Key cannot read a verdict from: a poisoning reported and no molecule found, a molecule found and no sourced route, a mark in a source list, a molecule known from this one species and not yet confirmed. The name is the stem of its recorded molecule, where the record names one and decides it, then investiganda, and nothing after it while the row is open. Where the record names no molecule the name is investiganda alone, and the gap is deliberate. The Key reads molecules: it puts a molecule in a name only when a record has placed that molecule in the mushroom. A poisoning report is not such a record; it says that harm occurred, not what caused it. The molecule may well exist, and the word states that it is to be found, not a guess at what it will be. The species is not innocuus, because innocuus means that the published record carries no link to a toxic molecule, and this species is on the table because the question of such a link is open; it would be innocuus only once the question is closed in that direction. The species leaves the table, and the word, by a ruling: its molecule registered and read, or its record found to carry no molecule after all. Latin, the gerundive of investigare: to be investigated.

On Needs Investigation, The Complete Table.

GBIF: photographs, names and where it has been found.

Sources

Li et al. 2021

3 reports of eating without harm

Li H, Tian Y, Menolli N Jr, Ye L, Karunarathna SC, Perez-Moreno J, Rahman MM, Rashid MH, Phengsintham P, Rizal L, Kasuya T, Lim YW, Dutta AK, Khalid AN, Huyen LT, Balolong MP, Baruah G, Madawala S, Thongklang N, Hyde KD, Kirk PM, Xu J, Sheng J, Boa E, Mortimer PE (2021). Reviewing the world's edible mushroom species: a new evidence-based classification system. Comprehensive Reviews in Food Science and Food Safety 20: 1982-2014. Supplementary Table S1. link

Boa E 2004

‘edible’ — Annex 3

Boa E R (2004). Wild edible fungi: a global overview of their use and importance to people. Non-Wood Forest Products 17. Rome: FAO. ISBN 92-5-105157-7. link

Wu et al. 2019

‘E’ — Wu et al. 2019, Table 1, p. 48: E (edible)

Wu F, Zhou L-W, Yang Z-L, Bau T, Li T-H, Dai Y-C (2019). Resource diversity of Chinese macrofungi: edible, medicinal and poisonous species. Fungal Diversity 98: 1-76. doi:10.1007/s13225-019-00432-7. Table 1, 'Medicinal fungi and their function(s)'. link

Needs Investigation. Why it is here: A record of poisonings: Suber 1938 (Westfälische Pilzbriefe 1: 47-48), two people ill about 3 h after a large portion, briefly parboiled, with vomiting and diarrhoea for two days; he reports several other poisonings. Stelin, who called it edible after boiling in 1936, reclassified it as poisonous in 1939. No molecule is named. (a published record). What would settle it: Search for an agent isolated from Tricholoma pessundatum, and for cases after 1938.

Cite this pageRubel, William. 2026. “Tricholoma pessundatum.” Taxonomy of Toxins. Last modified 24 October 2026. https://taxonomyoftoxins.com/species/tricholoma-pessundatum/