Cheirosporium L. Cai & K.D. Hyde
Index Fungorum number: IF 506570
Saprobic on submerged wood. Sexual morph: Undetermined. Asexual morph: Conidiomata sporodochial, scattered, punctiform, brown to black. Mycelium immersed or partly superficial, consisted of branched, septate, subhyaline to pale brown hyphae. Conidiophores semi-macronematous to macronematous, mononematous, flexuous, septate, unevenly branched, branches sterile or fertile; branches with an elongate, relatively enlarged, obclavate cell. Conidiogenous cells holoblastic, monoblastic, terminal, determinate. Conidia acrogenous, cheiroid, olivaceous to brown, solitary, dry, smooth- walled (Cai et al. 2008).
Type species: Cheirosporium triseriale L. Cai & K.D. Hyde, Persoonia 20: 56 (2008)
Notes: Cheirosporium differs from other genera in Dictyosporiaceae by its semi-macronematous to macronematous, branched conidiophores with sterile or fertile branches, on which grow an elongate, relatively enlarged, obclavate cell (Cai et al. 2008). Two species are listed in Index Fungorum (2020) and both are from freshwater habitats (Cai et al. 2008). Cheirosporium vesiculare Abdel-Aziz, with only LSU sequence deposited in GenBank, clustered with the type species C. triseriale with low bootstrap support in Abdel-Aziz (2016b) and they are unrelated in our phylo- genetic analysis (data not shown). Cheirosporium triseriale has punctiform sporodochia, complanate conidia with 1–2 cells per row, without appendages, while C. vesiculare has compact sporodochia, non-complanate conidia with 9–12 cells per row and with 2 to 5 large, globose to sub- globose appendages (Cai et al. 2008; Abdel-Aziz 2016b).
Key to freshwater Cheirosporium species (Dong et al. 2020)
1. Conidia 15–25 × 11–15 µm....................... C. triseriale
1. Conidia 42–65 × 19–22 μm...................... C. vesiculare
Abdel-Aziz FA (2016) Two new cheirosporous asexual taxa (Dictyosporiaceae, Pleosporales, Dothideomycetes) from freshwater habitats in Egypt. Mycosphere 7:448–457
Cai L., Guo X.Y., Hyde K.D. (2008) Morphological and molecular characterisation of a new anamorphic genus
Dong, W., Wang, B., Hyde, K.D., McKenzie, E.H.C., Bhat, D.J et al. (2020) Freshwater Dothideomycetes. Fungal Diversity