Phaeoisaria ellipsoidea R. Zhu & H. Zhang 2023, sp. nov.
Creators: name: Yang, Jun-Xian
name: Zhang, Huang
name: Wang, Lin
name: Zhu, Rong
name: Dong, Wei
name: Chen, Shou-Yue
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Fungi
Ascomycota
Dothideomycetes
Capnodiales
Mycosphaerellaceae
Phaeoisaria
Phaeoisaria ellipsoidea

description: Phaeoisaria ellipsoidea R. Zhu & H. Zhang, sp. nov.
FIGURE 2
Index Fungorum number: IF900262, Facesoffungi number: FoF 14019
Etymology: – In reference to the ellipsoidal conidia
Holotype: – IFRD 9462
Saprobic on decaying wood submerged in freshwater. Sexual morph:Undetermined. Asexual morph: Hyphomycetous. Synnemata 6–22(–28) μm wide (x = 12.8 μm, n = 10), erect, rigid, dark brown to black, velvety, smooth, composed of compactly and parallelly adpressed conidiophores, with flared conidiogenous cells in the above half. Conidiophores up to 1.2 mm long, macronematous, synnematous, branched, brown to black, with paler apical cells, smooth. Conidiogenous cells 5.5–13.5 × 2–5 μm (x = 9 × 3.5 μm, n = 20), polyblastic, terminal, discrete, recurved, smooth, sympodial, denticulate, each with several denticulate conidiogenous loci, subhyaline to light brown. Conidia 4–8 × 3–4.5 μm (x = 6.5 × 4 μm, n = 20), narrowly ellipsoidal to obovoid, rounded at the apex, hyaline, aseptate, guttulate, smooth.
Culture characteristics: Colonies on PDA reaching 30 mm diam. at 20–25˚C after 5 weeks. Surface gray flat, dry, rough, margin undulate and irregular, with sparse mycelium. Reverse dark brown to black.
Material examined: China, Yunnan Province, Xishuangbanna, Man Feilong reservoir, on submerged decaying wood of unidentified plants, 7 November 2020, R. Zhu, N 11 (IFRD 9462, holotype), ex-type living culture IFRDCC 3134.
Notes: The multi-locus phylogenetic analyses show that P. ellipsoidea forms a distinct lineage in Phaeoisaria and groups with P. clematidis, P. dalbergiae and P. laianensis (FIGURE 1). Comparing to the three species, P. ellipsoidea has the longest conidiophores (up to 1210 μm vs. 28–46 μm in P. clematidis vs. 10–50 μm in P. dalbergiae vs. 116–491 μm in P. laianensis) (Luo et al. 2018, Crous et al. 2021, Liu et al. 2022). Phaeoisaria ellipsoidea can be distinguished from P. clematidis and P. dalbergiae by different shape of conidia (narrowly ellipsoidal to obovoidal with rounded apex vs. narrowly obovoidal with tapering base in P. clematidis vs. subcylindrical to obovoid, tapering towards both ends in P. dalbergiae) (Luo et al. 2018). Additionally, P. ellipsoidea differs from P. laianensis in having slightly wider conidia (3–4.5 μm vs. 1.7–2.9 μm) (Liu et al. 2022). The strains MFLUCC 16-1273 and MFLUCC 17-1341 of P. clematidis have nearly identical nucleotides in ITS loci, which are 24 differences (3.8%, including 13 gaps) from P. ellipsoidea. There are 33 (4.9%, including 13 gaps) and 46 (6.9%, including 16 gaps) base pairs differences in ITS loci between P. ellipsoidea and P. dalbergiae, P. ellipsoidea and P. laianensis, respectively. Following the generally accepted norm that more than 1.5% of nucleotide differences in the ITS region is likely to be a new species, P. ellipsoidea is introduced as a new species (Jeewon & Hyde 2016).
description: Published as part of Yang, Jun-Xian, Zhang, Huang, Wang, Lin, Zhu, Rong, Dong, Wei & Chen, Shou-Yue, 2023, Phaeoisaria ellipsoidea (Pleurotheciaceae, Pleurotheciales, Sordariomycetes), a new lignicolous freshwater fungus from Xishuangbanna, Yunnan Province, China, pp. 19-30 in Phytotaxa 591 (1) on page 25, DOI: 10.11646/phytotaxa.591.1.2, http://zenodo.org/record/7784160