# Tylopilus
**Tylopilus** P. Karst. is a genus of bolete (pore-bearing fleshy mushroom with cap and thick stem) fungi in the family [Boletaceae](https://www.edgepedia.org/boletaceae), order Boletales, typified by the bitter bolete *[Tylopilus felleus](https://www.edgepedia.org/tylopilus-felleus)* (Bull.) P. Karst.[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC12595509/) The genus was proposed by Petter Adolf Karsten in 1881[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC12595509/) • [2](https://www.first-nature.com/fungi/tylopilus-felleus.php), and about 75 species have been reported worldwide, mostly from North America, Australia, Asia, Africa, and Europe.[3](https://www.sciencedirect.com/org/science/article/pii/S1314405718000563)
| Key fact | Detail |
|---|---|
| Classification | Fungi, Basidiomycota, Agaricomycetes, Boletales, Boletaceae[4](https://species.data.kew.org/species/18700) |
| Type species | *Tylopilus felleus* (Bull.) P. Karst., proposed as genus in 1881[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC12595509/) |
| Species count | About 75 species reported worldwide[3](https://www.sciencedirect.com/org/science/article/pii/S1314405718000563) |
| Traditional diagnostic feature | Pink to pinkish brown spore prints, with white, pinkish, purplish pink, reddish, reddish brown, or brownish hymenophores[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC12595509/) |
| Subgenera | Traditionally divided into *T.* subg. *Tylopilus* and *T.* subg. *Porphyrellus*, separated by spore wall color in KOH and IKI[3](https://www.sciencedirect.com/org/science/article/pii/S1314405718000563) |
| Phylogenetic status | The traditional broad concept of Tylopilus is polyphyletic, with species distributed across multiple lineages[3](https://www.sciencedirect.com/org/science/article/pii/S1314405718000563) • [5](https://wi.knaw.nl/images/ResearchGroups/Phytopathology/pdf/Nuhn%20et%20al%202013.pdf) |
## Morphology and identification
Species traditionally placed in Tylopilus have hymenophores (the spore-bearing pore surface) that are white, pinkish, purplish pink, reddish, reddish brown, or brownish, and they produce pink to pinkish brown spore prints.[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC12595509/) The type species, *T. felleus*, is recognized by a substantial reticulate stem, an extremely bitter taste, a pink pore surface, and brown to tan colors; its spores measure 10–16 × 3–4 µm and its spore print is brownish pink.[6](https://www.mushroomexpert.com/tylopilus_felleus.html) The bitter taste is the source of the epithet *felleus*, from the Latin *fel*, meaning bile.[2](https://www.first-nature.com/fungi/tylopilus-felleus.php)
The genus was traditionally divided into two subgenera. *T.* subg. *Tylopilus* is characterized by spores with pale cinnamon-yellow to pale yellow walls in KOH and IKI, and context that usually remains unchanging or rust colored on injury; *T.* subg. *Porphyrellus* has spores with dark brown walls in KOH and IKI, and context that usually turns blue-green on injury and then red-brown.[3](https://www.sciencedirect.com/org/science/article/pii/S1314405718000563)
## Taxonomic history and molecular revision
The bitter bolete was first described as *Boletus felleus* by Jean Baptiste François Pierre Bulliard in 1788, and Karsten transferred it to his new genus Tylopilus in 1881.[2](https://www.first-nature.com/fungi/tylopilus-felleus.php) Synonyms of the genus name include *Rhodoporus* Quél. ex Bataille, *Rhodobolites* Beck, and *Leucogyroporus* Snell.[4](https://species.data.kew.org/species/18700)
Molecular phylogenetic analyses based on multigene sequences showed that the original, broad concept of Tylopilus was polyphyletic, and many new genera have been proposed for species formerly placed in it.[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC12595509/) One analysis found that Tylopilus in the broad sense appeared in 11 different evolutionary lineages.[3](https://www.sciencedirect.com/org/science/article/pii/S1314405718000563) A phylogenomic study of the *T. alboater* complex examined specimens morphologically identified as *T. alboater* from Asia, North America, and Australia using a phylogenomic analysis of 45 genomes and a concatenated multilocus dataset (nrLSU, tef1-α, rpb1, rpb2). These specimens proved polyphyletic, clustering within the subfamily Boletoideae, and represent eight distinct species across five generic lineages, including the new genus *Neoporphyrellus* with the new species *N. sinoalboater* and the new combinations *N. alboater* and *N. atronicotianus*, plus two new species of *Abtylopilus* (*Ab. indonesiensis* and *Ab. australiensis*) and three known species in the genera *Anthracoporus*, *Indoporus*, and *Tylopilus*.[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC12595509/)
## Diversity and distribution
Tylopilus species occur on several continents. In the Neotropics, *T. griseiolivaceus* was described as new from a montane pine woodland in the [Dominican Republic](https://www.edgepedia.org/dominican-republic) and is also known from temperate coniferous forests in the southeastern United States; the related *T. leucomycelinus*, originally from [Central America](https://www.edgepedia.org/central-america), had its range expanded and an epitype proposed in the same study.[7](https://research.fs.usda.gov/treesearch/59299) Two further species, *T. dunensis* and *T. pygmaeus*, were described from the Northeastern Atlantic Forest of Brazil based on morphological and molecular evidence.[8](https://www.biotaxa.org/Phytotaxa/article/view/phytotaxa.316.3.4) In Asia, *T. neofelleus*, originally reported from Japan, was confirmed from southwestern China by ITS and LSU sequence data, and the holotype of the Chinese *T. microsporus* was shown to be conspecific with Japanese *T. neofelleus*, making it a posterior synonym; the Chinese *T. plumbeoviolaceoides* was confirmed as a distinct species.[9](https://www.sciencedirect.com/science/article/pii/S1340354014001065) *T. yangzhuliangii* was described from Hainan Province in tropical southern China based on morphological and phylogenetic evidence.[10](https://www.biotaxa.org/Phytotaxa/article/view/phytotaxa.543.2.4)
## Bitter taste and edibility
The type species is intensely bitter, and cooking only seems to enhance the bitter taste, so a single specimen mixed with edible boletes can make a whole dish inedible, although the fungus is not poisonous.[2](https://www.first-nature.com/fungi/tylopilus-felleus.php) In some countries *T. felleus* is dried and used as a substitute for pepper.[2](https://www.first-nature.com/fungi/tylopilus-felleus.php) Bitterness is a practical identification aid: a small piece of flesh tasted and spat out distinguishes bitter Tylopilus species from edible lookalikes such as *Boletus edulis*, which has similar reticulation on the stem but lacks the pink flush to the pore openings.[2](https://www.first-nature.com/fungi/tylopilus-felleus.php)
## References
1. [Li J, Halling RE, Osmundson TW, Yang ZL, Li Y-C (2025). Global diversity of the Tylopilus alboater complex (Boletaceae, Boletales): new genus and species, and typification of the name Boletus alboater. IMA Fungus 16: e159676.](https://pmc.ncbi.nlm.nih.gov/articles/PMC12595509/)
2. [Tylopilus felleus, Bitter Bolete mushroom, First Nature](https://www.first-nature.com/fungi/tylopilus-felleus.php)
3. [Two new species and one new record of the genus Tylopilus (Boletaceae) from Indian Himalaya with morphological details and phylogenetic estimations, ScienceDirect](https://www.sciencedirect.com/org/science/article/pii/S1314405718000563)
4. [Tylopilus, Kew Species Data portal](https://species.data.kew.org/species/18700)
5. [Nuhn et al. (2013). Phylogenetic overview of the Boletineae](https://wi.knaw.nl/images/ResearchGroups/Phytopathology/pdf/Nuhn%20et%20al%202013.pdf)
6. [Tylopilus felleus, MushroomExpert.Com](https://www.mushroomexpert.com/tylopilus_felleus.html)
7. [Gelardi et al. (2019). Tylopilus griseiolivaceus sp. nov. and T. leucomycelinus revisited from the Dominican Republic, Mycological Progress 18(8): 1039-1056](https://research.fs.usda.gov/treesearch/59299)
8. [Magnago et al. Two new Tylopilus species (Boletaceae) from Northeastern Atlantic Forest, Brazil, Phytotaxa](https://www.biotaxa.org/Phytotaxa/article/view/phytotaxa.316.3.4)
9. [New collection, iconography and molecular evidence for Tylopilus neofelleus (Boletaceae, Boletoideae) from southwestern China, ScienceDirect](https://www.sciencedirect.com/science/article/pii/S1340354014001065)
10. [Tylopilus yangzhuliangii (Boletaceae, Boletales), a new bolete from tropical China, Phytotaxa](https://www.biotaxa.org/Phytotaxa/article/view/phytotaxa.543.2.4)
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*Topic: Encyclopedia › Life and health › Microorganisms and fungi › Fungi and mycology › Basidiomycete taxa › Agaricomycetes › Boletales › Other Boletaceae genera › Tylopilus*
*Initially written Sep 17, 2026 · Reviewed: Oct 21, 2026 · Edited: Oct 15, 2026; Oct 21, 2026 · Last review: Oct 21, 2026*
*Copyright 2026 EdgeChat AI, a subsidiary of Biostate AI.*
License: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license