Plectronidiopsis Nag Raj, Can. J. Bot. 57(13): 1397 (1979)
Facesoffungi number: FoF 07499
Ascomycota, genera incertae sedis
Saprobic on culms of Hierochloe utriculata (Poaceae) (Nag Raj 1979). Sexual morph: undetermined. Asexual morph: Conidiomata black, acervular, solitary to gregarious, semi-immersed, linear or oval in outline, patelliform to scutelliform in section view, unilocular, setose. Ostiole absent. Conidiomatal setae pale brown to brown at the base, paler to hyaline towards apex, cylindrical, straight or curved, aseptate, marginal. Conidiomatal wall composed of thick-walled, pale brown cells of textura angularis in the basal layer, becoming darker at the originating of conidiomatal setae. Conidiophores arising from inner wall layer of basal stroma, hyaline, cylindrical to dolliform, septate, unbranched, smooth-walled. Conidiogenous cells hyaline, enteroblastic, annellidic, lageniform to subcylindrical, usually integrated, indeterminate, smooth-walled. Conidia hyaline, cylindrical, with attenuated apex and truncate base, 1-septate, smooth-walled, bearing apical, basal and lateral flexuous appendages, arising as tubular extensions of the conidium body. Apical appendage single; basal appendages 2–3, inserted slightly above the truncate base; lateral appendages 1–3, inserted mostly on the apical cell, occasionally with another on the basal cell just below the median septum (adapted from Nag Raj 1979, 1993).
Type species: Plectronidiopsis chilensis (Speg.) Nag Raj, Can. J. Bot. 57(13): 1397 (1979)
Notes: Nag Raj (1979) proposed Plectronidiopsis to accommodate a segregated species from Dilophospora, as P. chilensis. Dilophospora differs from Plectronidiopsis by its globose, glabrous conidiomata and 3-septate conidia with circumpolar and branched dichotomously or irregularly appendages. Plectronidiopsis can be confused with Dwayalomella in having acervular, setose conidiomata and hyaline, cylindrical, 1-septate conidia with appendages. However, the conidia of Plectronidiopsis are separated from those of Dwayalomella in the number and disposition of the filiform appendages. The annellidic conidiogenous cells in Plectronidiopsis also separate it from the phialidic ones in Dwayalomella. The genus is monotypic and no molecular data is available. It is necessary to collect fresh sample of Plectronidiopsis chilensis to place Plectronidiopsis in a natural group and delineate its boundaries.
Distribution: Chile (Nag Raj 1979).
Plectronidiopsis chilensis (redrawn from Nag Raj 1979) a Conidia. b Vertical section of a conidioma. c Enlarged view of a conidiomatal seta. d Conidiophores and developing conidia.
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