Ascoconidium

Fungalpedia – Note 3032, Ascoconidium

Citation when using this data: Wenping Wu et al. 2023 – Fungalpedia.

Index Fungorum, Facesoffungi, MycoBank, GenBank

Classification: Helotiaceae, Helotiales, Leotiomycetidae, Leotiomycetes, Pezizomycotina, Ascomycota, Fungi

Colonies black, erumpent. Anamorph: Conidiophores arising from a pseudoparenchamytous basal stroma and becoming erumpent through the periderm, simple, short, sparsely septate, terminating in a phialidic conidiogenous cell. Conidiogenous cells sessile, aggregated in densely packed sori, clavate to subcylindrical, brown, thick-walled. Conidia cylindrical, septate, hyaline, formed single and successively. Teleomorph: described under Sageria, see Funk 1975).

Ecology/substrate/host: Saprobe or minor pathogens on dead branches of trees such as Castanea dentata, Tsuga heterophylla etc.

Geographical distribution: Canada and USA (Nag Raj and Kendrick 1975; Verkley 1999).

Description and illustration: Seaver (1942); Funk (1966a, b, 1975); Nag Raj and Kendrick (1975).

Notes: Ascoconidium differs from Chalara s. lat. and Sporoschisma in several aspects, such as its phialides lack a well-differentiated venter and collarette, conidiogenous loci near the base of the phialide, thick-walled phialide ruptured at maturity by a vertical split at the apex (Funk 1966a, b; Nag Raj and Kendrick 1975). Two species, A. purpurascens and A. tsugae, are known for the genus and can be distinguished by septation and size of conidia. Both species are known with the Ascoconidium anamorphs and helotiaceous discomycete teleomorphs (Seaver 1942; Funk 1975; Verkley 1999; Johnston et al. 2014). The teleomorphs are helotiaceous discomycetes. It was recommended to protect the asexually typified Ascoconidium (1942) over sexually typified Sageria (1975) by Johnston et al. (2014). No DNA sequence was available for molecular phylogenetic analyses, thus its phylogenetic relationship with other chalara-like fungi remains to be studied in future.