Aschersonia Mont., Annls Sci. Nat., Bot., sér. 3 10: 121 (1848)
Sordariomycetes, Hypocreomycetidae, Hypocreales, Clavicipitaceae
Index Fungorum number: IF7236; 175 morphological species (Index fungorum 2020), 12 species with sequence data.
Parasitic on whiteflies and scale insects. Sexual morph: Stromata brightly pigmented, discoid to stud-shaped, scattered or aggregate, edge round, ostiolate, usually with fibrillose hypothallus, texture soft when fresh, superficial, epiphyllous or hypophyllous. Perithecia flask-shaped, immersed, slightly projecting. Asci cylindrical, with thickened cap. Ascospores hyaline, multi-septate, filiform to long fusiform, non-fragmenting (Chaverri et al. 2008). Asexual morph: Conidiomata orange to yellow, discoid to stud-shaped, scattered or aggregate, surface flatted, ostiolate. Ostioles dark brown, sunken. Conidiophores arising from the basal matrix of conidiomata, branched or unbranched, usually reduced to conidiogenous cells. Paraphyses filiform, aseptate, guttulate, longer than conidiophores. Conidiogenous cells cylindrical, hyaline, smooth-walled, guttulate, phialidic. Conidia unicellular, hyaline, fusiform, inequilateral, guttulate, singly producing from the tip of conidiogenous cells (Chaverri et al. 2008).
Type species: Aschersonia tahitensis Mont., Annls Sci. Nat., Bot., sér. 3 10: 122 (1848)
Notes: The genus comprises insect parasitic fungi. The sexual morphs are hypocrella-like
(Mongkolsamrit et al. 2009). Some species may control insect pests (Meekes et al. 2002, Wei et al. 2016). Rossman et al. (2016) recommended protecting Hypocrella over Aschersonia although Aschersonia is an earlier name. However, the name Aschersonia was wildly used and many molecular data were provided to the species of this genus. To respect the earlier name Aschersonia, we suggest preserving Aschersonia over Hypocrella. Species infect scale insect and whiteflies and produce bright, pulvinate or discoid stromata or conidiomata, superficial or embedded perithecia, cylindrical asci, non-disarticulating ascospores, and fusiform conidia with acute ends (Chaverri et al. 2008). (Adopted from Hyde et al. 2020)
Other species: Aschersonia insperata Rombach, M. Liu, Humber & K.T. Hodge
Chaverri P, Liu M, Hodge K. 2008 – A monograph of the entomopathogenic genera Hypocrella, Moelleriella, and Samuelsia gen. nov. (Ascomycota, Hypocreales, Clavicipitaceae), and their aschersonia-like anamorphs in the Neotropics. Studies in Mycology 60, 1–66.
Meekes ET, Fransen JJ, van Lenteren JC. 2002 – Pathogenicity of Aschersonia spp. against
whiteflies Bemisia argentifolii and Trialeurodes vaporariorum. Journal of Invertebrate Pathology 81, 1–11.
Hyde KD, Norphanphoun C, Maharachchikumbura SSN, Bhat D et al. 2020 – Refined families of Sordariomycetes. Mycosphere 11(1), 305–1059.
Mongkolsamrit S, Luangsa-Ard JJ, Spatafora JW, Sung GH et al. 2009 – A combined ITS rDNA and β-tubulin phylogeny of Thai species of Hypocrella with non-fragmenting ascospores. Mycological Research 113 (6-7), 684–699.
Rossman AY, Allen WC, Braun U, Castlebury LA et al. 2016 – Overlooked competing asexual and sexually typified generic names of Ascomycota with recommendations for their use or protection. IMAFungus 7, 285–304.
Wei X, Song X, Dong D, Keyhani NO et al. 2016 – Efficient production of Aschersonia placenta protoplasts for transformation using optimization algorithms. Canadian journal of microbiology 62, 579–587.