Triseptata Boonmee & Phookamsak, 2020

Boonmee, Saranyaphat, Calabon, Mark S., Phookamsak, Rungtiwa, Elgorban, Abdallah M. & Hyde, Kevin D., 2020, Triseptata sexualis gen. et sp. nov. in Latoruaceae (Pleosporales), Phytotaxa 447 (4), pp. 252-264 : 257

Triseptata Boonmee & Phookamsak , gen. nov.

Index Fungorum number: IF557185, Facesoffungi number: FoF07229

Etymology:—The generic epithet refers to consistent 3-septate ascospores.

Saprobic on dried branches of an unidentified plant. Sexual morph: Ascostromata immersed to slightly erumpent, visible as black spots, single or clustered, scattered or gregarious, uni- to multi-locular, globose to subglobose, with or without basal stroma, dark brown, obscure ostiole. Peridium composing several layers of textura angularis, with compressed of dark brown cells. Hamathecium comprising cylindrical, branched, septate, anastomosed, hyaline pseudoparaphyses. Asci 8-spored, bitunicate, fissitunicate, cylindrical-clavate, sessile, apically rounded. Ascospores 1–2-seriate, partially overlapping, ellipsoid-fusiform, straight or slightly curved, regularly 3–septate, darkened and constricted at the septa, the second cell from the top slightly wider than the others, asymmetrical ends, light brown to brown, smooth-walled. Asexual morph: hyphomycetous conidia-like structures in culture. Conidiophores and conidiogenous cells absent. Conidia superficial, globose to subglobose, multiseptate, brown to dark brown, smooth-walled.

Type species:— Triseptata sexualis Boonmee & Phookamsak

Notes:—The new genus Triseptata is characterized by immersed, uni- to multi-loculate ascomata, filamentous, pseudoparaphyses, bitunicate, fissitunicate, cylindrical-clavate asci and 3–septate, light-pigmented ascospores with asymmetrical ends in its sexual form. The asexual state was formed in culture and is hyphomycetous with superficial, globose to subglobose, multiseptate, dark-pigmented conidia ( Fig. 3 g-i). Triseptata has a distinctive morphology as compared to closely related genera in families Latoruaceae and Longipedicellataceae ( Upadhyay 1966, Ariyawansa et al. 2015, Crous et al. 2015, Sharma et al. 2015, Phukhamsakda et al. 2016, Tibpromma et al. 2017). Most genera in Latoruaceae are characterized by hyphomycetous asexual taxa and unknown sexual morph ( Upadhyay 1966, Crous et al. 2015, Sharma et al. 2015), excepted Pseudoasteromassaria was known sexaul morph connected with coelomycetous asexual form ( Ariyawansa et al. 2015, Tibpromma et al. 2017). Whereas, genera in Longipedicellataceae were known as aquatic fungi, characterized by having clavate asci with long pedicels, 2-celled, hyaline ascospores and their asexual morphs were known as chlamydosporous hyphomycetes ( Phukhamsakda et al. 2016).

Figures

FIGURE 3. Triseptata sexualis (MFLUCC 11–0002, ex-type). a Germinating ascospore.b, c Colonies on MEA from surface and reverse. d Aerial mycelium in culture. e, f Development of conidia in culture. g–i Close up of conidia–like structures. Scale bars: a = 5 µm, d = 10 µm, f = 10 µm, g–i = 20 µm.