Arxiella Papendorf, Trans. Br. mycol. Soc. 50(1): 73 (1967).
MycoBank number: MB 7233; Index Fungorum number: IF 7233; Facesoffungi number: FoF 08091; 3 morphological species (Species Fungorum 2020), 3 species with molecular data.
Type species: Arxiella terrestris Papendorf, Trans. Br. mycol. Soc. 50(1): 73 (1967).
Notes: Species of Arxiella have been reported with asexual morphs (Papendorf 1967; Crous et al. 2014). Arxiella terrestris and A. lunata have hyphomycetous characters, while A. dolichandrae has coelomycetous characters. Coelomycetous Arxiella is characterized by sporodochial, brown conidiomata on agar surface, with globose to somewhat elongated, phialidic, brown conidiogenous cells, and reniform, medianly 1-septate conidia, with guttulate, horn like appendages at the ends (Crous et al. 2014). Hyphomycetous Arxiella is characterized by septate, branched, hyaline to slightly olivaceous hyphae, with 1- to multi-celled, all cells conidiiferous conidiophores, and reniform, ends obliquely cornute, 1-septate, hyaline to slightly coloured conidia, on short or elongate sterigma-like projections, single or in short chains or in small irregular groups (Papendorf 1967). Arxiella was treated as incertae sedis by Crous et al. (2014). Crous et al. (2018a) showed the placement of Arxiella within Muyocopronaceae. Subsequently, this was supported by Hernández-Restrepo et al. (2019) who provided a phylogenetic tree from four loci (ITS, LSU, rpb-2, and tef1) and concluded that this genus should be placed in Muyocopronaceae.