Kirschsteiniothelia longiconidiophora 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): 6535 (2024)

Index Fungorum number: IF902422; MycoBank number: MB902422; Facesoffungi number: FoF16095

Etymology – Referring to the longer conidiophores of the species in Kirschsteiniothelia.

Holotype – HKAS 131379

Saprobic on submerged decaying wood. Asexual morph: Colonies effuse, hairy, scattered, brown to dark brown. Mycelium immersed, composed of pale brown, septate, unbranched hyphae. Conidiophores 150–560 × 2.2–4.3 µm (x̅ = 288.4 × 3.3 µm, n = 20), macronematous, mononematous, erect, smooth, pale brown to brown, septate, unbranched, cylindrical, straight or slightly flexuous, slightly inflated at the apex. Conidiogenous cells (15–) 23–36 × (2.1–) 2.9–4.9 (–5.5) µm (x̅ = 26.1 × 3.9 µm, n = 20), monoblastic, terminal, integrated, determinate, subcylindrical, brown. Conidia 19–32 (–44) × 4.2–7.2 µm (x̅ = 27.6 × 5.9 µm, n = 15), acrogenous, solitary, dry, obclavate, 3–4- distoseptate when mature, smooth, straight or slightly curved, pale brown to brown or olive green, rounded apical sometimes with a rounded, gelatinous sheath, truncate and with thickened scar at the base. Sexual morph: Undetermined.

Culture characteristics – Conidia germinating on PDA within 12 h, and germ tubes produced from both ends. Colonies on PDA reaching 10 mm diameter after 3 weeks at room temperature. Mycelium dry, dense, colonies on the surface of PDA, protrusion, with regular edges, pale brown to dark brown, the lower layer is dark green, velvety. Reverse dark green, smooth.

Material examined – China, Yunnan Province, Wenshan Zhuang and Miao Autonomous Prefecture, Bamei Town, on submerged decaying wood, 7 February 2022, W.P. Wang, S-3771 (HKAS 131379, holotype), ex-type living cultures CGMCC 3.25432 = KUNCC 23–14559; ibid., S3508 (HKAS 131378, paratype), ex-paratype living culture KUNCC 23–13756.

Notes – Phylogenetic analysis showed that Kirschsteiniothelia longiconidiophora (CGMCC 3.25432 and KUNCC 23–13756) clustered with K. cangshanensis with 96% ML/1.00 PP support (Fig. 2). Kirschsteiniothelia longiconidiophora resembles K. cangshanensis in having unbranched, cylindrical conidiophores, solitary, obclavate conidia with a gelatinous sheath at the apex. However, K. longiconidiophora can easily be distinguished from K. cangshanensis in having much longer conidiophores, which are slightly inflated at the apex (150–560 × 2.2–4.3 vs. 105.5–135.5× 6–8 µm) (Bao et al. 2018). A comparison of ITS and LSU sequence data indicated that the type strain of K. longiconidiophora (CGMCC 3.25432) differs from K. cangshanensis in 4.24% (20/472 bp) and 0.13% (1/767 bp), respectively.

Figure 1 – Kirschsteiniothelia longiconidiophora (HKAS 131379, holotype). a Colonies on the substratum. b Conidiophores. c–f Conidiophores with conidia. g–i Conidiogenous cells with conidia. j, k Conidia. l Germinating conidium. m, n Colonies on PDA from surface and reverse. Scale bars: b–d = 40 µm, e = 60 µm, f = 100 µm, g–i = 15 µm, j–l = 10 µm.

Figure 2 – RAxML tree based on analysis of Kirschsteiniotheliaceae that combined LSU, ITS, and SSU dataset. The combined analyses include 68 strains with 2133 characters, including gaps (LSU: 803 bp, ITS: 491 bp, and SSU: 839 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 Pseudorobillarda eucalypti (MFLUCC 12–0417) and P. phragmitis (CBS 398.61). The new collections are indicated in red. Ex-type strains are indicated with “T” after the strain number.