Tubeufia geniculata

Tubeufia geniculata (C.H. Kuo & Goh) Y.Z. Lu & K.D. Hyde

≡ Helicomyces geniculatus C.H. Kuo & Goh, Mycoscience (2018)

Index Fungorum number: IF 554914; Facesoffungi number: FoF 04820

Etymology: geniculatus, referring to the distinct geniculation of conidiophores.

Holotype: TNM F31100

Sexual morph Undetermined. Asexual morph Colonies on natural substratum effuse, white, arachnoic, ceraceous, coarsely flocculose, forming cottonlike mycelium layer. Mycelium mostly superficial, partly immersed, composed of branched, septate, subhyaline to pale brown, smooth hyphae. Stalked sclerotia often present, yellowish brown to medium brown, spherical, muriform, 14–23.5 µm in diam. Setae arising from superficial mycelium, branched, multiseptate, up to 120 µm long, 4–6 µm wide, uniform in width, subhyaline to pale brown, gradually becoming hyaline toward the rounded apex, sterile or bearing conidiophores. Conidiophores macronematous, mononematous, arising as lateral branches from creeping hyphae or as a single lateral branch from the setae, short, unbranched, distinctly geniculate due to sympodial proliferation of conidiogenus cell, subhyaline

to very pale brown, 5–8-septate, 23–50 µm long, 4–6 µm wide. Conidiogenous cells polyblastic, sympodial. Conidia acrogenous, dry, holoblastic, attached eccentrically, seceding schizolytically

from conidiogenous cells and leaving a refractive scar on the conidiogenous loci, hyaline, hygroscopic, 29–36 µm in diam.

Material examined: CHINA, Taiwan, Chiayi County, Juchi Township, on decaying wood submerged in a freshwater stream, 5 February 2017, Chang-Hsin Kuo, NCYU-U2-1 (TNM F31100, holotype).

Notes: This species was introduced as Helicomyces geniculatus by Kuo and Goh (2018) based on phylogeny and morphology. However, we compare its morphology with our new collections and other known Helicomyces species, and its morphology does not correspond to the generic concept of Helicomyces but fits well into Tubeufia. Furthermore, our phylogenetic result shows that two isolates of H. geniculatus (BCRC FU30849 and NCYU U2-1B) cluster within Tubeufia and share a sister relationship to Tubeufia abundata with good bootstrap support, and phylogeny support that they are distinct species (Lu et al. 2018). Therefore, we synonymize it under Tubeufia as T. geniculata. (Lu et al. 2018)

Freshwater distribution: Taiwan, China (Kuo and Goh 2018; Lu et al. 2018)