Pseudohelicoon subglobosum

Pseudohelicoon subglobosum (Goh & C.H. Kuo) Y.Z. Lu & K.D. Hyde

Basionym: Helicoon subglobosum Goh & C.H. Kuo [as ‘Helicoön’], Phytotaxa 346(2): 145 (2018)

Index Fungorum number: IF554921; Facesoffungi number: FoF 04816

Holotype: TNM F31003

Etymology: referring to the subglobose shape of the conidia

Sexual morph: Undetermined. Asexual morph: Colonies on natural substratum dark-brown, somewhat glistening, effuse. Mycelium partly immersed but mostly superficial, consisting of branched hyphae and short conidiophores bearing conidia; superficial hyphae ca 3.5−5.5 µm wide, pale yellowish-brown, smooth, branched, closely septate, slightly constricted at the septa which are 11.7−18 µm apart. Conidiophores macronematous, mononematous, cylindrical, erect, straight, arising as short branches more or less at right angles to the subtending hyphae, mid yellowish-brown or somewhat darker than the subtending hyphae, unbranched, non-septate, smooth, 11−19 µm long, (4.5−)5−6.5 µm wide. Conidiogenous cells monoblastic, integrated, terminal, determinate. Conidia solitary, dry, acrogenous, medium brown, helicoid, filament (6.5−)7.5−9.5 µm wide, smooth, distinct multiseptate, slightly constricted at the septa, tightly coiled (7−)8(−9) times in a clockwise direction to form a subglobose or broadly elliptical body, (57−)66−78(−87.5) µm long, (44−)58−72.5(−77) µm wide, with a length to width ration of (0.9−)1.1(−1.3), usually incorporated with mucilaginous substances such that no gaps are visible between adjacent coils, non-hygroscopic; conidial secession schizolytic at the deliminating septum of the conidiogenous cell, giving rise to a short pedicel of (7−)8−12.5 long and 5−6.5 µm wide at the base. (Description from Goh and Kuo 2018)

Material examined: CHINA, Taiwan, Chiayi County, Juchi Township, on decaying wood submerged in a freshwater stream, 5 Feb 2017, Chang-Hsin Kuo, NCYU-K3-2 (holotype: TNM F31003). Ex-type culture BCRC FU30843.

Notes: This taxon was introduced as Helicoön subglobosum by Goh and Kuo (2018). We synonymize it under Pseudohelicoon subglobosum based on phylogenetic evidence. (Notes from Lu et al. 2018)

Freshwater distribution: Taiwan, China (Goh and Kuo 2018)