Tetraploa longiappendiculata W.P. Wang, H.W. Shen, K.D. Hyde & Z.L. Luo, in Wang, Hyde, Bao, Wanasinghe, Lin, Shen, Lu, Zhang, Su, Li, Al-Otibi, Yang & Luo, Mycosphere 15(1): 6564 (2024)

Index Fungorum number: IF902426; MycoBank number: MB902426; Facesoffungi number: FoF16098

Etymology – Referring to the conidia with longer appendages of this fungus.

Holotype – HKAS 131398

Saprobic on submerged decaying wood. Asexual morph: Colonies effuse, dark brown, messy. Mycelium superficial, composed of branched, septate, smooth, subhyaline hyphae. Conidiophores absent. Conidiogenous cells indistinct. Conidia 26–39 × 16–32 µm (x̅ = 33.7 × 24.3 µm, n = 30), nearly short cylindrical, narrow at the base, solitary, straight, inconspicuous euseptate, verrucose, brown to dark brown, rarely guttulate, composed of 3–4 columns when mature, 3–4-septate in each column, with 3–4 appendages. Appendage 110–180 µm long (x̅ = 140.4 µm, n = 20), 4.6–8.4 µm wide at the base, 1.2–3.1 µm wide at the apex, green to brown, euseptate, smooth, straight, rigid, guttulate. Sexual morph: Undetermined.

Culture characteristics – Conidia germinating on PDA within 12 h, and germ tubes produced from the apex of appendage. Colonies on PDA reaching 15 mm diameter after 2 weeks of incubation at room temperature. Mycelium dry, dense, colonies on the surface of PDA, with regular edges, circular, with protuberance, grey to brown. Reverse circular, edges are grey and the center is brown, smooth.

Material examined – China, Yunnan Province, Wenshan Zhuang and Miao Autonomous Prefecture, Bamei Town, on submerged decaying wood, 28 February 2023, W.P. Wang, S-4338 (HKAS 131398, holotype), ex-type living cultures CGMCC 3.25433 = KUNCC 23–13397.

Notes – The phylogenetic analysis showed that Tetraploa longiappendiculata (CGMCC 3.25433) is sister to Tetraploa sp. (KT 2578) with 100 ML/1.00 PP support (Fig. 2). Tetraploa sp. (KT 2578) was introduced by Tanaka et al. (2009). This specimen has a similar morphology to T. ellisii and T. sasicola (basionym: Tetraplosphaeria sasicola), but Tanaka et al. (2009) did not give a definitive identification of this specimen. Tetraploa longiappendiculata is different from Tetraploa sp. (KT 2578) in having smaller conidia (26–39 × 16–32 vs. 38–50 × 22–33 µm), and shorter (110– 180 vs. 142–330 µm) appendages (Tanaka et al. 2009). Tetraploa longiappendiculata can be distinguished from T. ellisii by the number of conidial columns (3–4 vs. 4) and shorter conidia (26– 39 vs. 30–51 µm).

Figure 1 – Tetraploa longiappendiculata (HKAS 131398, holotype). a Colonies on the substratum. b–f conidia. g Germinating conidium. h, i Colonies on PDA from surface and reverse. Scale bars: b, c = 15 µm, d–g = 30 µm.

Figure 2 – RAxML tree based on analysis of Tetraplosphaeriaceae that combined LSU, ITS, and SSU dataset. The combined analyses include 43 strains with 2358 characters, including gaps (LSU: 844 bp, ITS: 523 bp, and SSU: 991 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 Muritestudina chiangraiensis (MFLUCC 17–2551). The new collection is indicated in red. Ex-type strains are indicated with “T” after the strain number.