Pseudorobillarda parasiamensis N. Tangthirasunun, W.J. Li & K.D. Hyde, sp. nov.
Index Fungorum number: IF557162, Facesoffungi number: FoF 07564
Etymology: Referring to its morphology similar to P. siamensis, but phylogeny distinct.
Saprobic on dead leaves. Sexual morph: undetermined. Asexual morph: Conidiomata 140–160 µm diam., 100–130 µm high, black, foliicolous, scattered, with the venter immersed in the host leaf and only part of the top of the long, rostrate ostiolar neck protruding above the surface of the leaf, subglobose to obclavate in section view, unilocular, thick-walled, glabrous, ostiolate. Ostiole single, subcylindrical to obconic, centrally located, with a very long ostiolar canal. Conidiomatal wall 20–30 µm thick, composed of thick-walled, brown to hyaline cells of textura angularis. Conidiophores reduced to conidiogenous cells. Conidiogenous cells 5–10 × 2–4 µm, hyaline, enteroblastic, phialidic, subcylindrical, sometimes proliferating 2–3 times, thick- and smooth -walled. Conidia 15–23 × 6–8 µm ( = 20 × 7 µm; n = 30), hyaline, fusiform to ellipsoidal, rounded at apex, truncated at base, unicellular, guttulate, thick-walled, smooth, bearing 2–4-unbranched, flexuous, acellular appendages in the upper half of apical part (12–23 µm long).
Material examined: Thailand, Nakhonratchasima, Khao Yai, on unidentified dead leaves, 16 June 2012, N. Tangthirasunun NTCL082-3 (MFLU 13–0273, holotype).
Notes: Strain MFLUCC 12–0414 was identified as Pseudorobillarda siamensis by Tangthirasunun et al. (2014). This strain is morphologically related to P. siamensis, as both have pycnidial conidiomta with long subcylindrical to obconic ostiolar neck and fusiform to broadly ellipsoidal conidia. However, MFLUCC 12–0414 has slightly shorter conidia and is 0–3-septate whereas P. siamensis conidia are 20–26 × 6–7.5 µm (av. 22.6 × 6.8 µm) and aseptate. Phylogenetically these two strains are distinct from each other (Fig. 304)
Pseudorobillarda parasiamensis (MFLU 13–0275, holotype) a Herbarium specimen. b, c Appearance of black conidiomata with rostrate ostiolar neck protruding above the surface of the leaf. d Vertical section of conidioma. e, f Vertical sections of peridium. g–i Conidiogenous cells and developing conidia (arrow shows annellide). j–s Conidia. Scale bars d = 100 µm, e–f = 20 µm, g–s = 10 µm.
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.