Helicoarctatus
Helicoarctatus Y.Z. Lu, J.C. Kang & K.D. Hyde
Index Fungorum number: IF 554830; Facesoffungi number: FoF 04707
Etymology: “Helicoarctatus” referring to tightly helicoid conidia.
Saprobic on submerged decaying wood. Sexual morph: Undetermined. Asexual morph: Hyphomycetous, helicosporous. Colonies on the substratum superficial, effuse, gregarious, white. Mycelium composed of partly immersed, partly superficial, brown to dark brown, septate, branched hyphae, with masses of crowded, glistening conidia. Conidiophores macronematous, mononematous, setiform, cylindrical, unbranched, septate, tapering towards apex, brown to dark brown, smooth-walled. Conidiogenous cells holoblastic, mono- to polyblastic, determinate, discrete, denticulate, arising laterally from lower portion of the conidiophores as tiny tooth-like protrusions, with each bearing 1–2 tiny sporogenous conidiogenous loci, hyaline, smooth-walled. Conidia solitary, pleurogenous, helicoid, rounded at tip, multi-septate, tightly coiled 3–4 times, will not becoming loosely in water, guttulate, hyaline, smooth-walled. (Lu et al. 2018)
Type species: Helicoarctatus aquaticus Y.Z. Lu, J.C. Kang & K.D. Hyde
Notes: The monotypic genus Helicoarctatus is characterized by setiform conidiophores, discrete conidiogenous cells arising laterally from lower portion of the conidiophores, with each bearing 1–2 tiny conidiogenous loci, which are similar to Helicosporium Nees (Lu et al. 2018). Helicoarctatus differs from Helicosporium by larger conidia and molecular characters (Lu et al. 2018). The type species H. aquaticus formed a sister clade with a sexual morphic species Neohelicoma fagacearum (Boonmee & K.D. Hyde) Y.Z. Lu with high bootstrap support (Lu et al. 2018). Helicoarctatus aquaticus and N. fagacearum are separated as distinct genera based on phylogenetic analysis (Lu et al. 2018). (Notes from Dong et al. 2020)
List of freshwater Helicoarctatus species
Helicoarctatus aquaticus Y.Z. Lu, J.C. Kang & K.D. Hyde, Fungal Diversity 92: 166 (2018)
Freshwater distribution: Thailand (Lu et al. 2018)
References
Dong W, Wang B, Hyde KD, McKenzie EHC, Raja HA, Tanaka K, Abdel-Wahab MA, Abdel-Aziz FA, Doilom M, Phookamsak R, Hongsanan S, Wanasinghe DN, Yu X-D, Wang G-N, Yang H, Yang J, Thambugala KM, Tian Q, Luo Z-L, Yang J-B, Miller AN, Fournier J, Boonmee S, Hu D-M, Nalumpang S, Zhang H (2020) Freshwater Dothideomycetes. Fungal Divers 105:319–575. https://doi.org/10.1007/s13225-020-00463-5
Lu YZ, Liu JK (Jack), Hyde KD, Jeewon R, Kang JC, Fan C, Boonmee S, Bhat DJ, Luo ZL, Lin CG, Eungwanichayapant PD (2018) A taxonomic reassessment of Tubeufiales based on multi-locus phylogeny and morphology. Fungal Divers 92:131–344. https://doi.org/10.1007/s13225-018-0411-y
Recent Genus
1Neochlamydotubeufia
Neohelicomyces
Recent Species
Neohelicomyces submersusNeohelicomyces hyalosporus
Neohelicomyces grandisporus