Aquasubmersa K.D. Hyde & Huang Zhang, Cryptog. Mycol. 33(3): 340 (2012).
Index Fungorum number: IF 800875; MycoBank number: MB 800875; Facesoffungi number: FoF 07118; 2 morphological species (Species Fungorum 2020), 2 species with molecular data.
Saprobic on submerged wood in freshwater habits Sexual morph: Ascomata dark brown to black, solitary to gregarious, immersed to semi-immersed, subglobose, unilocular, glabrous, short papillate, ostiolate. Peridium composed of thick-walled, dark brown to pale brown cells of textura angularis. Hamathecium comprising asci and pseudoparaphyses. Pseudoparaphyses hyaline, subcylindrical, branched, septate. Asci 8-spored, bitunicate, cylindrical, pedicellate, rounded at apex, with an ocular chamber. Ascospores biseriate, hyaline, broadly fusiform with rounded ends, straight or slightly curved, with a median septum, constricted at the septum, enclosed by a gelatinous sheath (adapted from Ariyawansa et al. 2015). Asexual morph: Conidiomata dark brown to black, pycnidial, subperidermal, solitary, semi-immersed, subglobose to ellipsoidal, unilocular, glabrous, thick-walled, ostiolate. Conidiomatal wall composed of dark brown to pale brown, thick-walled cells of textura angularis to textura prismatica. Conidiophores arising from inner layer cells of conidiomata, when present, subcylindrical to doliiform, unbranched, septate. Conidiogenous cells hyaline, holoblastic, subcylindrical to lageniform, determinate, discrete or indiscrete, thick and smooth-walled. Conidia hyaline, ellipsoidal, rounded at both ends, or sometimes with papillate bases, smooth, thick-walled, guttulate, with or without gelatinous sheath.
Type species – Aquasubmersa mircensis Huang Zhang & K.D. Hyde.
Notes – Aquasubmersa was established by Zhang et al. (2012a), with the asexual type species A. mircensis. Ariyawansa et al. (2015a) introduced the second species, A. japonica, with sexual and asexual morphs. This genus was placed in Lophiotremataceae by Doilom et al. (2016). Phylogenetic analyses using ITS, LSU, rpb-2, SSU, and tef1 sequence data support this genus as a sister clade of Lophiotremataceae and Cryptocoryneaceae (Hashimoto et al. 2017b).
Distribution – Japan, Thailand (Zhang et al. 2012a, b; Ariyawansa et al. 2015).