Fungalpedia –Note 26 Roselymyces
Roselymyces Fiúza, C.R. Silva, R.F. Castañeda & Gusmão
Index Fungorum number: IF822003; Fig. 1
The monotypic genus Roselymyces was introduced by Fiuza et al. (2018) as incertae sedis in Xylariales, Sordariomycetes. This genus is typified by R. brasiliensis Fiúza, C.R. Silva, R.F. Castañeda & Gusmão, which was isolated on dead submerged and terrestrial leaves of Calophylum brasiliense in Brazil. Roselymyces brasiliensis was found on green leaves, after incubation in litter bags (Fiuza et al. 2018). Therefore, it may be an endophytic species (Fiuza et al. 2018). However, further research is required to confirm the ecology of Roselymyces. Only the asexual state has been reported in Roselymyces and the stroma was absent. Roselymyces is similar to members of Beltraniaceae: Beltraniella Subram, Hemibeltrania Piroz, Parapleurotheciopsis P. M. Kirk and Pseudobeltrania Henn (Fiuza et al. 2018). Roselymyces is characterized by terminal, integrated and subhyaline conidiogenous cells. Conidia are terminal, naviculate to subcylindrical, smooth-walled, asepate or septate, rounded at apex, subhyaline and arranged in short branched or unbranched chains (Fiuza et al. 2018). Roselymyces have conidiophores arising from lobed basal cells, sympodial extension and tiny refractive denticulate conidiogenous cells (Fiuza et al. 2018) as found in Beltraniella, Hemibeltrania, Parapleurotheciopsis and Pseudobeltrania (Seifert et al. 2011). However, Beltraniella and Pseudobeltrania differ from Roselymyces by the absence of biconic conidia with a hyaline equatorial band (Seifert et al. 2011). Roselymyces is distinct from Parapleurotheciopsis by its polyblastic conidiogenous cell (Kirk 1982). Roselymyces differs from Hemibeltrania by having navicular to subcylindrical conidia, while the conidia in the latter are ellipsoid, obovate or limoniform (Fiuza et al. 2018). Roselymyces clustered with Polyscytalum Riess, Pseudoidriella Crous & R.G. Shivas, Cylindrium Bonord and Tristratiperidium Daranag., Camporesi & K.D. Hyde with high support in the phylogenetic analysis of ITS and LSU sequences (Fiuza et al. 2018). Roselymyces brasiliensis is similar to Polyscytalum species (P. algarvense, P. purgamentum), Pseudoidriella syzygii and Cylindrium species (C. aeruginosum, C. elongatum) by having sympodial extension of the conidiophore (Fiuza et al. 2018). However, Roselymyces brasiliensis differs from these three genera by having lobed basal cells and ramoconidia (Fiuza et al. 2018). Tristratiperidium is also distinct from Roselymyces by phialidic conidiogenous cells (Fiuza et al. 2018).
Type species: Roselymyces brasiliensis Fiuza, C.R. Silva, R.F. Castañeda & Gusmão
Fig 1. Roselymyces brasiliensis (HUEFS 209016, holotype) a. Conidiophores in a group. b, c. Conidiophore. d. Conidia and conidiogenous cells. e. Conidia chain. f. Ramoconidia. g. Conidia. Scale bars: a–c = 20 μm, d–g = 10 μm. Redrawn from Fiuza et al. (2018).
Fiuza PO, Silva CR, Santos TAB, Raja H et al. 2018 – Roselymyces, a new asexual genus of the Xylariales (Ascomycota) from Brazil. Sydowia 70, 59–65. http://www.sydowia.at/s yd70/T5-Fiuza.htm
Kirk PM. 1982 – New or interesting microfungi. Transactions of the British Mycological Society, 78(1), 55–74. https://sci-hub.se/https:/doi.org/10.1016/S0007-1536 (82)80077-6
Seifert KA, Morgan-Jones G, Gams W, Kendrick WB. 2011 – The genera of Hyphomycetes. CBS Biodiversity Series no. 9. Utrecht, CBS-KNAW Fungal Biodiversity Centre. https://www.ingentaconnect.com/content/nhn/pimj/2011/00000027/00000001/art00008
S. A. Dilini Thakshila, Center of Excellence in Fungal Research, School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand
(Edited by Chitrabhanu S. Bhunjun and Kevin D. Hyde)
Published online 18 May 2023