Fungalpedia – Note 574, Platycarpa
Platycarpa Couch
Citation when using this data: Zhang et al. 2025 (in prep.) – Fungalpedia, Basidiomycota.
Index Fungorum, Facesoffungi, MycoBank, GenBank, Fig. 1
Classification: Eocronartiaceae, Platygloeales, Incertae sedis, Pucciniomycetes, Pucciniomycotina, Basidiomycota, Fungi
Platycarpa was established by Couch (1949) to accommodate two species: Platycarpa boliviensis and P. polypodii. Platycarpa boliviensis was later synonymized under Ptechetelium cyatheae, the type genus of Ptechetelium, based on parasitic patterns and morphological characteristics (Oberwinkler and Bandoni 1984). Currently, only the type species of Platycarpa polypodii is accepted in this genus without available molecular data, and it is placed in Eocronartiaceae of the order Platygloeales (Pucciniomycetes, Basidiomycota) based on morphology (Bauer et al. 2006; Wijayawardene et al. 2022; Hyde et al. 2024c). Platycarpa polypodii (Bas. Septobasidium polypodii) was excluded from Septobasidium due to the distinctive feature that all Septobasidium species live with scale insects (Boedijn and Steinmann 1931; Couch 1938, 1949). Platycarpa polypodii is known only from its type material (Couch 1949; Oberwinkler and Bandoni 1984), which were reported as parasites in fern sporangia, with effused, flattened basidiocarps (fruit bodies) as small whitish to cream-colored patches covering the sori; thick-walled, interwoven hyphae without gelatinization; subglobose, hyaline probasidia with thickened walls; and cylindric or curved, 1-septate basidiospores (Oberwinkler and Bandoni 1984; Couch 1949). More collections with isolations, along with identification of their host are needed to provide molecular data, and clarify host relationships.
Type species: Platycarpa polypodii (Couch) Couch.
≡ Septobasidium polypodii Couch.
Other accepted species: Species Fungorum – search Platycarpa.
Figure 1 – Platycarpa polypodii. a Diagrammatic section of fertile leaflet of Polypodium sp. showing sporangial sorus, and fructification of Platycarpa Polypodii. b Section through basidiocarp showing thick-walled hyphae, probasidia, basidia in different developmental stages and basidiospores germinating by repetition. Redrawn from Couch (1949), and Oberwinkler and Bandoni (1984).
References
Boedijn KB, Steinmann A 1931 – Les especes des genres Helicobasidium et Septobasidium des Indes Neerlandaises. Bull Jard Bot Buitenzorg III Ser 11:165–219.
Couch JN 1938 – The genus Septobasidium. University of North Caroline Press.
Couch JN 1949 – The taxonomy of Septobasidium polypodii and S. album. Mycologia 41:427–441.
Hyde KD, et al. 2024c – The 2024 outline of fungi and fungus-like taxa. Mycosphere (in press).
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