Fungalpedia – Note 263, Chamonixia


Chamonixia Rolland.

            Citation if using this entry: Khyaju et al. 2024 (in prep.) Basidiomycota 4.

Index Fungorum, FacesofFungi, Mycobank, GenBank Fig.1

Classification: Boletaceae, Boletales, Agaricomycetidae, Agaricomycetes, Agaricomycotina, Basidiomycota, Fungi

            Chamonixia Rolland was established by Rolland (1899), which accommodated Chamonixia caespitosa Rolland from France as the type species (Mleczko et al. 2009Orihara et al. 2016). Chamonixia is a sequestrated descendant of epigeous boletes (Orihara et al. 2016). Chamonixia is characterized by gasterioid, spongy, white, fibrillose basidiomata, which often turn blue when bruised (Rolland 1899, Mleczko et al. 2009, Orihara et al. 2016). The hymephore is located in small round to oval chambers, initially pale turning brown, and lacking a stipe (Rolland 1899, Mleczko et al. 2009, Orihara et al. 2016). Basidia are mostly 4-spored and elliptic, brown, with 6–12 large, blunt, and longitudinal irregular ridges of basidiospores (Lebel et al. 2012, Orihara et al. 2016). Chamonixia has four developmental steps identical to those of Suillus and Boletinus, and basidiomata are exocarpic, claustropileate, and amphicleistoblemate (Clemincon 2005, Mleczko et al. 2009).

            Chamonixia is polyphyletic with Chamonixia s. str. from Europe and North America, and the remaining species found in Asia, Japan, and China were transferred to another genus, Rossbeevera T. Lebel & Orihara (Lebel et al. 2012, Orihara et al. 2016). Index Fungorum (2024) reports a total of 10 records of Chamonixia, whereas Wijayawardene et al. (2022) accepted only eight species. Lebel et al. (2012) carried out morphological and phylogenetic analysis (ITS, LSU) of Chamonixia species and found affinities with Leccinum and Leccinellum. Orihara et al. (2016) used morphological and phylogenetic analyses (ITS) to distinguish Chamonixia species. Regarding conservation, the type species Chamonixia caespitosa is often considered rare and is listed as an endangered species in the USA and many European countries (Mleczko et al. 2009, Orihara et al. 2016).

            Synonymy: Hymenogaster caespitosus (Rolland) Soehner,

                               Leccinum caespitosum (Rolland) M. Kuo & B. Ortiz

Type species: Chamonixia caespitosa Rolland 1899

            Other accepted species: (Species Fungorum – search Chamonixia)

Figure 1  Chamonixia caespitosa. a Basidiomata. b Section through hymenium & subhymenium with basidia & sterile elements. c Basidia. d Basidiospores. e Hyphae on the peridium surface. Scale bar: a = 1cm, b−e = 10 µm. Photo credit: follow the original literature by drawn from Mleczko et al. (2016).



Clémençon H 2005 − New observations on the basidiome ontogeny of Chamonixia caespitosa (sequestrate Boletaceae). Persoonia-Molecular Phylogeny and Evolution of Fungi, 18(4), 499−504.

He MQ, Zhao RL, Hyde KD, Begerow D, et al. 2019 − Notes, outline, and divergence times of Basidiomycota. Fungal Diversity, 99, 105−367.

Lebel T, Orihara T, Maekawa N 2012 − The sequestrate genus Rosbeeva T. Lebel & Orihara gen. nov. (Boletaceae) from Australasia and Japan: new species and new combinations. Fungal Diversity, 52, 49−71.

Mleczko P, Kozak M, Lawrynowicz M, Górszczyk A 2009 − New localities of Chamonixia caespitosa [hypogeous Boletaceae] in Central Europe. Acta Mycologica, 44(1), 29−42.

Orihara T, Ohmae M, Yamamoto K 2016 − First report of Chamonixia caespitosa (Boletaceae, Boletales) from Japan and its phylogeographic significance. Mycoscience, 57(1), 58−63.

Rolland ML 1899 − Excursion a Chamonix. Bulletin de la Societe mycologique de France 15, 73−78

Wijayawardene NN, Hyde KD, Al-Ani LKT, Tedersoo L, et al. 2020 – Outline of Fungi and fungus-like taxa. Mycosphere, Journal of Fungal Biology, 11(1), 1060–1456.


Entry by:

Sabin Khyaju, Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai, Thailand


(Edited by Thatsanee Luangharn, Samaneh Chaharmiri-Dokhaharani, & Achala R. Rathnayaka)


Published online 21 May 2024