Leptoxyphium Speg., Physis, Rev. Soc. Arg. Cienc. Nat. 4(no. 17): 294 (1918)
Facesoffungi number: FoF 06949
Dothideomycetes, Dothideomycetidae, Capnodiales, Capnodiaceae
Saprobic on sugary exudates from insects growing on the surface of living leaves. Thallus composed of grey brown to brown, cylindrical, branched, septate, network-like mycelium. Sexual morph: undetermined. Asexual morph: Conidiomata grey-brown, synnematous, gregarious, superficial, arising from aggregated hyphae, base bulbous, comprising parallel hyphae, straight to slightly flexuous, sometimes with helical twisting, differentiated into a basal stalk and a funnel-shaped, cupulate head. Stalk and pycnidial wall composed of thick-walled, dark brown to brown cells of textura porrecta. Conidiophores formed on inner layers of pycnidial wall. Conidiogenous cells not observed. Conidia hyaline, ellipsoid, unicellular, smooth-walled, eguttulate (Hughes 1976, Chomnunti 2011).
Type species: Leptoxyphium graminum (Pat.) Speg., Physis, Rev. Soc. Arg. Cienc. Nat. 4(no. 17): 294 (1918)
Notes: Twenty taxa are accepted in Leptoxyphium, but few have been studied with molecular data (Cheewangkoon et al. 2009, Crous et al. 2011b, Chomnunti 2011, Yang et al. 2014). Chomnunti (2011) regarded Leptoxyphium as a separate genus in Capnodiaceae based on LSU and SSU sequence data. The phylogeny derived from a LSU, SSU and ITS dataset shows that our strain (MFLUCC 14-0189/UiTM05) clustered with L. cacuminum (MFLUCC10-0049, MFLUCC10-0086, MFLUCC 10-0059), L. glochidion (IFRDCC 2651) and L. fumago (CBS 123.26) (Fig. 53). Comparison of LSU, SSU and ITS sequence data of these strains show they are conspecific. The sequence similarities among these strains are shown in table 7. They share a similar form of pycnidia and conidia, and the only difference among these strains are pycnidial and conidial dimensions (Table 8). However, this difference is considered to be intraspecies variation. The name Leptoxyphium fumago has priority, thus L. cacuminum and L. glochidion are reduced to synonymy with L. fumago.
Distribution: Australia, China, Madagascar, Thailand (Cheewangkoon et al. 2009, Crous et al. 2011a, Chomnunti et al. 2011, Yang et al. 2014)
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.