Sterigmatobotrys rudis (Sacc.) Heuchert, U. Braun & Ertz

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, Phytotaxa 591 (1), pp. 19-30 : 25-27

Sterigmatobotrys rudis (Sacc.) Heuchert, U. Braun & Ertz , Fungal Biology 120(11): 1423 (2016).

FIGURE 3

Basionym: Septonema rude Sacc., Michelia 1: 270 (1878).

Synonymy: Taeniolella rudis (Sacc.) S. Hughes, Canad. J. Bot. 36: 817 (1958).

Saprobic on decaying wood submerged in freshwater. Sexual morph: Undetermined. Asexual morph: Hyphomycetes. Colonies on substratum superficial, effuse, scattered, black, slightly shiny, long chains of conidia, erect, in small tufts or procumbent on the substrate. Mycelium immersed, sometimes superficial, composed of branched, subhyaline to pale brown hyphae. Conidiophores almost indistinguishable from conidia but the conidiophores are usually attached to the substrate and only rarely detached. Conidiogenous cells monoblastic, integrated, terminal, monopodial, subcylindrical or doliiform, cylindrical, brown. Conidia catenate, in unbranched chains, not easily disintegrating, conidia longadhering, chains at least up to 167 µm long, 4.0–5.5 µm wide in constricted or narrow segments between single conidia, maximum width 7–12.5 µm, straight or slightly flexuous, individual conidia obclavate, ellipsoid, fusiform, 26–52 × 9.5–13.5 µm (x = 37.8 × 12 μm, n = 30), 3–10-septate, not constricted at the septa, septa conspicuously thickened, dark brown, somewhat paler at the apex, smooth.

Culture characteristics: Colonies on PDA reaching 40 mm diam. at 20–25˚C after 30 days. Surface raised in center, red brown. Reverse dark brown, with regular margin. Conidia germinating on PDA within 24 h. Germ tubes produced from the conidial base.

Material examined: China, Yunnan Province, Xishuangbanna, Man Feilong Reservoir , on dead submerged decaying wood of unidentified plants, 7 November 2020, R. Zhu, N 39 IFRD 500-42 , living culture IFRDCC 3135 .

Notes: Taeniolella rudis was introduced by Hughes (1958). Recently, T. rudis was transferred to Sterigmatobotrys as S. rudis by Ertz et al. (2016) according to the phylogenetic and morphological analyses. Our collection fits well with S. rudis in all morphological characteristics (Ertz et al. 2016). There are only one and two nucleotides differences in LSU and ITS gene respectively between our collection and the reference specimen DAOM 229838. Therefore, we identify the new isolate as S. rudis .

Figures

FIGURE 3. Sterigmatobotrys rudis (IFRD 500-42) a, b Colonies on natural substrate. c–g Conidiophores with adhering conidia. h Apical region of conidia. i–o Conidia and fragments of conidial chains. p Germinated conidium. q Colony on PDA (from front). r Colony on PDA (from reverse). Scale bars: c = 20 μm, d, f, g = 30 μm, e = 50 μm, h–p = 10 μm.