Aquasubmersa K.D. Hyde & Huang Zhang, Cryptog. Mycol. 33(3): 340 (2012)
Dothideomycetes, Pleosporomycetidae, Pleosporales, Aquasubmersaceae
Saprobic on submerged wood in freshwater habit. 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 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 K.D. Hyde & Huang Zhang, Cryptog. Mycol. 33(3): 340 (2012)
Notes: Ariyawansa et al. (2015) added a second species A. japonica A. Hashim. & Kaz. Tanaka, which has both the sexual and asexual morph. They also showed that Aquasubmersa is close to Lophiotrema (Lophiotremataceae) based on analysis of SSU, LSU and ITS sequence data, but it is distinguished by conidiomata form. Aquasubmersa was assigned to a new family Aquasubmersaceae (Pleosporales) based on SSU, ITS, LSU, tef1, rpb2 sequence data.
Distribution: Japan, Thailand.
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: pages279–80.