Pseudoplagiostoma Cheew., M.J. Wingf. & Crous, in Cheewangkoon, Groenewald, Verkley, Hyde, Wingfield, Gryzenhout, Summerell, Denman, Toanun & Crous, Fungal Diversity 44: 96 (2010)
Diaporthomycetidae, Annulatascales, Pseudoplagiostomataceae, Pseudoplagiostoma
Pathogenic on leaves, making spots. Sexual morph: Ascomata brown to black, perithecial, immersed in host tissues, slanted to horizontal, globose to elliptical, coriaceous, ostiolate, papillate. Papilla erumpent, internal wall lined by hyaline periphyses. Peridium containing a few layers of thick-walled, brown cells of textura angularis. Paraphyses absent. Asci 8-spored, unitunicate, subcylindrical to long obovoid, sessile, apex blunt, with wedge-shaped, J-, subapical ring. Ascospores hyaline, overlying uniseriate to biseriate, fusiform to ellipsoid, narrowing towards the rounded ends, 1-septate, with terminal, elongate, hyaline appendages. Asexual morph: Coelomycetous. Conidiomata acervular to pycnidial, subcuticular to subepidermal. Peridium containing brown, small cells of textura angularis. Conidiophores absent. Conidiogenous cells cylindrical to ampulliform, enteroblastic, proliferating with periclinal thickening. Conidia brown to hyaline, holoblastic, ellipsoid, unicellular, with thick apex and a flat swelling scar at the base (adapted from Maharachchikumbura et al. 2016).
Type species: Pseudoplagiostoma eucalypti Cheew., M.J. Wingf. & Crous, in Cheewangkoon, Groenewald, Verkley, Hyde, Wingfield, Gryzenhout, Summerell, Denman, Toanun & Crous, Fungal Diversity 44: 98 (2010)
Notes: Pseudoplagiostoma is a foliar pathogen of Eucalyptus with astromatic, slanted to horizontal, globose perithecia lacking paraphyses, with aseptate ascospores with terminal, elongate, hyaline appendages and a cryptosporiopsis-like asexual morph. Cryptosporiopsis eucalypti falls in Diaporthales in the phylogenetic analyses using combined gene analysis of ITS and tub2 gene sequence data which resolved the species in Pseudoplagiostoma (Cheewangkoon et al. 2010). A newly added species is P. dipterocarpi, an asexual endophyte isolated from the leaves of Dipterocarpus tuberculatus in Chiang Mai, Thailand (Suwannarach et al. 2016). The asexual morph of Pseudoplagiostoma mangiferae isolated from a living leaf of Mangifera in Yunnan, China was introduced by Phookamsak et al. (2019) based on the morphology and phylogenetic analyses of a combined ITS, LSU, tub2 and tef1 dataset.
Species illustrated in this entry
Pseudoplagiostoma eucalypti Cheew., M.J. Wingf. & Crous
Pseudoplagiostoma mangiferae Dayarathne, Phookamsak & K.D. Hyde
Cheewangkoon R, Groenewald JZ, Verkley GJM, Hyde KD et al. 2010 – Re-evaluation of Cryptosporiopsis eucalypti and Cryptosporiopsis-like species occurring on Eucalyptus leaves. Fungal Diversity 44, 89–105
Maharachchikumbura SSN, Hyde KD, Jones EBG, McKenzie EHC et al. 2016 – Families of Sordariomycetes. Fungal Diversity 79, 1–317
Phookamsak R, Hyde KD, Jeewon R, Bhat DJ et al. 2019 – Fungal diversity notes 929–1035: taxonomic and phylogenetic contributions on genera and species of fungi. Fungal Diversity 95, 1–273
Suwannarach N, Kumla J, Lumyong S. 2016 – Pseudoplagiostoma dipterocarpi sp. nov., a new endophytic fungus from Thailand. Mycoscience 57, 2