Clypeispora A.W. Ramaley, Mycotaxon 40: 13 (1991).
Index Fungorum number: IF 11280; Facesoffungi number: FoF 08595, 1 morphological species (Species Fungorum 2021), molecular data unavailable.
Pathogenic on host. Spots angular, bounded by veins, uniformly red-brown, visible on both sides of the leaf. Mycelium immersed, hyaline, septate, branched, composed of cells ca 2–3 wide. Conidiomata amphigenous, pycnidial, immersed, black at the surface of the host, hyaline to golden elsewhere, substomatal, unilocular, up to 180 µm in diameter, more or less globose at maturity, thin-walled, ostiolate; wall composed of one layer of cells with nearly hyaline to golden walls, black adjacent to the host epidermis; ostiole circular, central, papillate early, papilla often not present at maturity. Conidiophores absent. Conidiogenous cells forming the conidiomatal wall, holoblastic, discrete, determinate, monosporous, nearly hyaline to golden-walled at the base; 4-7 µm wide at the more or less thick-walled base, each bearing a thin-walled, conical to threadlike projection on the inner surface from which the conidia arise. Conidia hyaline, allantoid, smooth, aseptate, bluntly rounded at the apex and base, often with an irregular apical and or basal appendage (Adapted from Ramaley 1991).
Type species: Clypeispora angustifoliorum A.W. Ramaley
Notes: Clypeispora resembles several coelomycetes genera such as Neottiospora, Pseudorobillarda, Tiarospora, Giula, Torosporiopsis, Pseudobasidiospora in having mature conidia bearing a non-cellular apical and/ or basal appendage. Clypeispora differs from Tiarospora in that the former produce monosporous conidiogenous cells and Tiarospora has monosporous or sympodial conidiogenous cells. Clypeispora differs from Neottiospora and Pseudorobillarda in that both the latter show phialidic conidiogenous cells producing multiple spores from a single locus. The other genera have monosporous conidiogenous cells but compared to Clypeispora, the conidiogenous cells form a distinct layer lining the conidiomatal cavity or occur on thin-walled conidiophores (Torosporiopsis). Clyspeispora can also be differentiated from Septoriella, Tiarospora and Torosporiopsis in having brown septate conidia. Like Clypeispora, members of Giulia and Tiasrosporella are characterized by hyaline, aseptate conidia, but their appendages are limited to the conidial apex. Clypeispora differs from Neottiosporina in conidial septation and differs from Pseudobasidiospora in that the latter has an excentric apiculus ending in a truncate scar and the conidiogenous cells have a distinctive excentric apex. Clypeispora is currently considered as a doubtful genus in Mycosphaerellaceae. Fresh collection is needed to resolve the taxonomic placement.