Aschersonia Mont., Annls Sci. Nat., Bot., sér. 3 10: 121 (1848) = Underwoodina Kuntze, Revis. gen. pl. (Leipzig) 3(3): 538 (1891)
Sordariomycetes, Hypocreomycetidae, Hypocreales, Clavicipitaceae
Saprobic or parasitic on scale insects and whiteflies. Sexual morph: see Chaverri et al. (2008). Asexual morph: Conidiomata reddish brown, formed from the body of an insect, stromatic, pycnidial, rounded or irregular in shape, multilocular, with immersed, globose, subglobose or obpyriform locules arranged peripherally in the same plane or irregularly in the inner stroma, glabrous, with or without ostiole. Conidiomatal wall composed of thick-walled, brown to hyaline cells. Paraphyses arising from the inner wall layer of locules, hyaline, filiform, tapered towards apex. Conidiophores reduced to conidiogeneous cells. Conidiogenous cells hyaline, enteroblastic, phialidic, cylindrical to subcylindrical, determinate, smooth-walled. Conidia hyaline, fusiform, straight or slightly curved, thick- and smooth-walled, guttulate, often in brightly colored mass, extruded in copious slime.
Type species: Aschersonia tahitensis Mont., Annls Sci. Nat., Bot., sér. 3 10: 122 (1848)
Notes: Aschersonia, Moelleriella and Samuelsia are entomopathogenic fungi (Chaverri et al. 2008). They are similar in having stromatic, pycnidial, multilocular conidiomata, hyaline, filiform paraphyses and enteroblastic, phialidic conidiogenous cells. Aschersonia and Moelleriella have fusiform conidia, while Samuelsia has allantoid conidia Chaverri et al. 2008; Tibpromma et al. 2017). Aschersonia was separated from Moelleriella by its sexual morph. Ascospores of Moelleriella usually disarticulate at maturity inside the ascus, whereas the ascospores of Aschersonia do not disarticulate inside the ascus (Chaverri et al. 2008). Aschersonia was initially recognized as plant parasites (Montagne 1848; Parkin 1906). However, it was reported as entomopathogenic by Webber (1897), and confirmed by Petch (1925). Accounts of the taxonomic history and phylogeny of Aschersonia were provided by Obornik et al. (1999), Sung et al. (2007a, b) and Hyde et al. (2020). Synonym of Aschersonia was provided by Kuntze (1891) as Underwoodina. Hypocrella was considered as the sexual morph of Aschersonia and the preferred name (Rossman et al. 2016a, b). However, Hyde et al. (2020) preferred Aschersonia over Hypocrella as Aschersonia was the earlier name.
Distribution: Argentina, Australia, Brazil, Britain, Canada, Columbia, China, Cuba, Dominican, Ecuador, Guyana, India, Indonesia, Japan, Mauritius, Malaysia, Mexico, Netherlands, New Zealand, Papua New Guinea, Philippines, Poland, Puerto Rico, Senegal, Sir Lank, Sudan, Thailand, USA, Venezuela, Vietnam.
Li WJ, McKenZie EHC, Liu JK, Bhat DJ, Dai DQ, Caporesi E, Tian Q, Maharachcikumbura SSN, Luo ZL, Shang QJ, Zhang JF, Tangthirasunun N, Karunarathna SC, Xu JC, Hyde KD (2020) Taxonomy and phylogeny of hyaline-spored coelomycetes. Fungal Diversity 100: pages279–801.