Torula chinensis W.H. Tian, Y.P. Chen & Maharachch. J. Fungi 9, 150, 6 (2023)
Index Fungorum number: IF847014; MycoBank number: MB847014; Facesoffungi number: FoF16099
Saprobic on submerged decaying wood. Asexual morph: Colonies superficial, effuse, dense, velvety, brown to black. Mycelium mostly immersed, composed of septate, branched, smooth, subhyaline hyphae. Conidiophores 13–25 (–47) × 1.8–2.8 µm (x̅ = 22.8 × 2.3 µm, n = 10), semimacronematous, mononematous, erect, straight or slightly flexuous, smooth, cylindrical, pale brown to brown, septate, partly reduced to conidiogenous cells, doliiform at the apex. Conidiogenous cells 5.2–7.3 × 4.1–6.9 µm (x̅ = 6.5 × 5.9 µm, n = 20), monoblastic, terminal, brown to dark brown, dry, minutely verrucose, doliiform to subglobose or cupulate. Conidia 15–50 (–90) × 4.3–7.9 µm (x̅ = 32.6 × 6.3 µm, n = 50), mostly solitary, and sometimes catenate, straight or slightly curved, brown to dark brown, verrucose, dry, rounded at both ends, monilioid composed of subglobose cells, 6–17- septate, constricted at septum, guttulate. Sexual morph: Undetermined.
Culture characteristics – Conidia germinating on PDA within 12 h, and germ tubes produced from both ends. Colonies on PDA reaching 20 mm diameter after 2 weeks of incubation at room temperature. Mycelium dry, dense, colonies on the surface of PDA, with regular edge, basal layer is light brown gelatinous, and covered with white, velvety hyphae. Reverse circular, pale brown to brown, smooth.
Material examined – China, Yunnan Province, Wenshan Zhuang and Miao Autonomous Prefecture, Bamei Town, on submerged decaying wood, 7 February 2022, W.P. Wang, H-697 (HKAS 130434).
Notes – Phylogenetic analysis showed that our new collection clustered with Torula chinensis with 79% ML/0.98 PP support (Fig. 2). The LSU and ITS sequences of our new collections showed 99.88% (803/804 bp) and 99.8% (490/491 bp) similarity with the holotype of T. chinensis. Our new collection (HKAS 130434) resembles T. chinensis in having straight or slightly flexuous conidiophores with doliiform conidiogenous cells at the apex, and solitary or catenate, monilioid conidia. We therefore recognize our new collections as T. chinensis.
Figure 1 – Torula chinensis (HKAS 130434). a, b Colonies on the substratum. c–h Conidiophores with conidiogenous cells. i–p conidia. q Germinating conidium. r, s Colonies on PDA from surface and reverse. Scale bars: c–e = 5 µm, f−h, k–m, q = 10 µm, i, j, n–p = 20 µm.
Figure 2 – RAxML tree based on analysis of Torulaceae that combined ITS, LSU, tef1-α, SSU, and rpb2 dataset. The combined analyses include 69 strains with 4166 characters, including gaps (ITS: 554 bp, LSU: 806 bp, tef1-α: 812 bp, SSU: 979 bp, and rpb2: 1015 bp). Bootstrap support values for maximum likelihood (ML) greater than 75% and Bayesian posterior probabilities greater than 0.95 are indicated above branches as ML/PP. The tree is rooted with Neooccultibambusa thailandensis (MFLUCC 16–0274) and Occultibambusa bambusae (MFLUCC 13–0855). The new collections are indicated in red. Ex-type strains are indicated with “T” after the strain number