Fungalpedia – Note 221, Guestia


Guestia G.J.D. Sm. & K.D. Hyde

Index FungorumFacesoffungiMycoBank, GenBank, Fig. 1

Citation when using this entryLi et al. 2024 (in prep) – Fungalpedia,  Xylariomycetidae. 

Classification: Xylariaceae, Xylariales, Xylariomycetidae, Sordariomycetes, Pezizomycotina, Ascomycota, Fungi

Guestia was introduced by Smith & Hyde (2001) in Xylariaceae based on morphology with G. gonetropospora as the type species. This genus consists with only one species (Species Fungorum 2024), which has been reported as saprobe collected from dead rachis of Mauritia flexuosa (palm) in Ecuador. Guestia is characterized by pseudostromata with 1–4 ascomata, black, conical, or hemispherical stromata, with a thin and patchy, 8-spored, unitunicate asci with amyloid apical rings, inequilateral ascospores, and dark germ slit (Smith & Hyde 2001). Wendt et al. (2018) accepted Guestia within the Xylariales genera incertae sedis based on only known morphological descriptions of the conidial states and this taxonomic placement confirmed by Hyde et al. (2020) and Wijayawardene et al. (2020, 2022). No DNA sequence data are available for the type species in NCBI (; accessed on February 2024). 

Type speciesGuestia gonetropospora G.J.D. Sm. & K.D. Hyde


Figure 1 –  Guestia gonetropospora. a Section of stroma. b, c Asci. d Ascospores. Scale bars: a = 100 μm, b–d = 10 μm. Redrawn from Smith & Hyde (2001).



Hyde KD, Norphanphoun C, Maharachchikumbura SSN, Bhat DJ et al. 2020 – Refined families of Sordariomycetes. Mycosphere 11(1), 305–1059.

Smith GJD, Hyde KD. 2001 – Fungi from palms. XLIX. Astrocystis, Biscogniauxia

CyanopulvisHypoxylonNemaniaGuestiaRosellinia and Stilbohypoxylon. Fungal Diversity 7, 89–127. 

Wendt L, Sir EB, Kuhnert E, Heitkämper S et al. 2018 – Resurrection and emendation of the Hypoxylaceae, recognised from a multigene phylogeny of the Xylariales. Mycological Progress 17, 115–154. 

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

Wijayawardene NN, Hyde KD, Dai DQ, Sánchez-García M et al. 2022 – Outline of Fungi and fungus-like taxa – 2021. Mycosphere 13, 53–453. 


Entry by 

Yanxia Li and Mingkwan Doilom, Innovative Institute for Plant Health/ Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China, Ministry of Agriculture and Rural Affairs, Zhongkai University of Agriculture and Engineering, Guangzhou, 510225, China.


(Edited by Kevin D Hyde, Mingkwan Doilom, Samaneh Chaharmiri-Dokhaharani, & Achala R. Rathnayaka)