Polyphialoseptoria Quaedvl., R.W. Barreto, Verkley & Crous, Stud. Mycol. 75: 355 (2013)
Facesoffungi number: FoF 07511
Dothideomycetes, Dothideomycetidae, Capnodiales, Mycosphaerellaceae
Parasitic on the host plant in terrestrial habitat. Sexual morph: undetermined. Asexual morph: Conidiomata brown, pycnidial, solitary to gregarious, immersed to erumpent, globose, unilocular, glabrous, ostiolate. Ostiole circular, centrally located. Conidiomatal wall composed of thick-walled, brown to pale brown cells of textura angularis. Conidiophores arising from the inner wall layer of conidiomata, hyaline, cylindrical, branched, septate, smooth-walled. Conidiogenous cells hyaline, phialidic or sympodial, subcylindrical to ampulliform, determinate or indeterminate, discrete or integrated. Conidia hyaline, scolecosporous or cylindrical to subcylindrical, with subobtuse apex, irregularly curved, multi-septate, smooth-walled, granular to guttulate (adapted from Quaedvlieg et al. 2013).
Notes: Polyphialoseptoria was introduced to accommodate two septoria-like taxa, P. tabebuiae-serratifoliae Quaedvlieg, Alfenas & Crous collected on Tabebuia serratifolia (Bignoniaceae) and P. terminaliae collected on Terminalia catappa (Combretaceae) (Quaedvlieg et al. 2013). The third species, P. natalensis Crous, was described from an unidentified plant in South Africa (Crous et al. 2018b). These species are associated with leaf spots. We examined a herbarium specimen, which shows a similar form of conidiomata and conidia with Polyphialoseptoria species, but unlike the previously described species it has phialidic conidiogenous cells.
Based on a megablast search of NCBIs GenBank nucleotide database, the closest hits using the ITS sequence had highest similarity to Polyphialoseptoria natalensi (GenBank NR_161137; Identities = 463/478(97%), 4 gaps (0 %)), P. terminaliae (GenBank NR_156559; Identities = 451/463(97%), 3 gaps (0 %)), Septoria sp. (GenBank DQ897651; Identities = 457/473(97%), 3 gaps (0 %)), and P. tabebuiae-serratifoliae (GenBank NR_156558; Identities = 437/452(97%), 2 gaps (0 %)). However, as our strain lacks LSU sequence and other gene regions (e.g., rpb2, tef1 and tub2), we cannot confirm its placement. Thus this species was kept as Polyphialoseptoria sp.
Distribution: Brazil, South Africa, Thailand (Quaedvlieg et al. 2013, Crous et al. 2018b, this study).
Li WJ, McKenZie EHC, Liu JK, Bhat DJ, Dai DQ, Caporesi E, Tian Q, Maharachcikumbura SSN, Luo ZL, Shang QJ, Zhang JF, Tangthirasunun N, Karunarathna SC, Xu JC, Hyde KD (2020) Taxonomy and phylogeny of hyaline-spored coelomycetes. Fungal Diversity 100: pages279–801.