Fungalpedia – Note 561, Griggsia
Griggsia F. Stevens & Dalbey
Citation when using this data: Zhang et al. 2025 (in prep.) – Fungalpedia, Ascomycota.
Index Fungorum, Facesoffungi, MycoBank, GenBank, Fig. 1
Classification: Incertae sedis, Incertae sedis, Incertae sedis, Dothideomycetes, Pezizomycotina, Ascomycota, Fungi
Based on its unique morphology, Griggsia was introduced by Stevens and Dalbey (1919) to accommodate a parasite on the leaves of Cyathea arborea (Cyatheaceae, tree fern) from Puerto Rico, named Griggsia cyathea. The monotypic genus Griggsia was initially placed under Dothideomycetes, genera incertae sedis due to the mycelial character being in a stroma (Stevens and Dalbey 1919). However, based on a morphological reexamination of Griggsia cyathea, Thambugala et al. (2014) argued that Griggsia should be located in Sordariomycetes, genera incertae sedis, due to its unitunicate asci (Hyde et al. 2013) and this is also followed in the latest Outline of Fungi and fungus-like Organisms (Hyde et al. 2024c). Griggsia exhibits both sexual and asexual states. The sexual morph is characterized by superficial ascomata, filamentous, unbranched, septate, pseudoparaphyses, unitunicate, broadly obovoid asci, and broadly oval, hyaline, 1-celled ascospores (Stevens and Dalbey 1919; Thambugala et al. 2014). The asexual morph is characterized by coelomycetous features, including epidermal, dimidiate conidiomata, phialidic, integrated conidiogenous cells with a short collarette at the tip, and broadly obovoid to pyriform conidia (Stevens and Dalbey 1919; Thambugala et al. 2014). Molecular data is not available for this genus. Therefore, the type species, G. cyathea needs to be restudied and re-analyzed with fresh collections and isolations, epitypified and subjected to phylogenetic analysis. Lastly, it is not meaningful to discuss host preference based on the single specimen. Thus, more samples of Griggsia are needed to explore its ecology, as well as its host-specificity or preference.
Type species: Griggsia cyathea F. Stevens & Dalbe.
Other accepted species: Species Fungorum – search Griggsia.
Figure 1 – Griggsia cyathea (a–e Sexual morph, f–j Asexual morph). a Appearance of sexual state on host. b Peridium. c Ascospore. d, e Mature asci. f Appearance of asexual state on host. g Section through fruiting body. h Peridium. i Conidiogenous cell with conidia. j Conidia. Scale bars: a, f = 200 µm, b, g = 50 µm, c, h, j = 10 µm, d = 30 µm, e, i = 20 µm. Redrawn from Thambugala et al. (2014).
References
Hyde KD, et al. 2024c – The 2024 outline of fungi and fungus-like taxa. Mycosphere (in press).
Stevens FL, Dalbey N 1919 – A parasite of the tree fern (Cyathea). Bot Gaz 68:222–225.
Entry by
Jing-Yi Zhang, School of Food and Pharmaceutical Engineering, Guizhou Institute of Technology, Guiyang, 550025, People’s Republic of China, Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai, 57100, Thailand, School of Science, Mae Fah Luang University, Chiang Rai, 57100, Thailand, Guizhou Key Laboratory of Agricultural Microbiology, Guizhou Academy of Agricultural Sciences, Guiyang, 550009, People’s Republic of China.
Published online 11 June 2025