Dictyocheirospora appendiculata 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): 6542 (2024)
Index Fungorum number: IF902423; MycoBank number: MB902423; Facesoffungi number: FoF16096
Etymology – Referring to the conidia with appendages of this fungus.
Holotype – HKAS 131353
Saprobic on submerged decaying wood. Asexual morph: Hyphomycetous. Colonies superficial, punctiform, dark brown. Mycelium mostly immersed, composed of subhyaline, smooth, thin-walled, septate hyphae. Conidiophores micronematous, mononematous, subhyaline, smooth, thin-walled. Conidiogenous cells 6.1–14 × 3.4–6.5 µm (x̅ = 9.8 × 4.6 µm, n = 15), holoblastic, integrated, terminal, determinate, subhyaline to pale brown, smooth, thin-walled. Conidia 50–80 × 17–30 µm (x̅ = 66.6 × 22.6 µm, n = 40), solitary, cheiroid, fusiform to cylindrical, subhyaline to pale brown, sometimes olive green, not complanate, composed of 4–7 rows of cells, rows digitate, cylindrical, slightly inwardly curved or straight at the tip, arising from a basal cell, each row with 9–11 cells, euseptate, sometimes distoseptate, constricted at the septum, with or without 1–2 hyaline, thin-walled, easy to rupture and shrink, globose to subglobose appendages at the apex to middle, 10.3–18 × 7.1–12 µm wide. Sexual morph: Undetermined.
Culture characteristics – Conidia germinating on PDA within 12 h, and germ tubes produced from the base. Colonies on PDA reaching 45 mm diameter after 4 weeks at room temperature. Mycelium dry, dense, colonies on the surface of PDA, it is a round pie-like projection, with irregular edges, flat surface, grey to brown, and the edges are orange. Reverse orange, with dark brown in the center, smooth, circular, split in the center.
Material examined – China, Yunnan Province, Wenshan Zhuang and Miao Autonomous Prefecture, Bamei Town, on submerged decaying wood, 28 February 2023, W.P. Wang, S-4356 (HKAS 131353, holotype), ex-type living culture KUNCC 23–13714.
Notes – Phylogenetic analysis showed that Dictyocheirospora appendiculata (KUNCC 23– 13714), D. multiappendiculata, and D. suae grouped in the same clade (Fig. 2). The three species share similar characteristics in having cheiroid, cylindrical, acomplanate, euseptate conidia with hyaline, globose to subglobose subapical appendages. However, D. appendiculata differs from D. multiappendiculata in having larger conidia (50–80 × 17–30 vs. (50–)55–62(–68) × (–16)19–22(– 24) µm) with fewer appendages (Shen et al. 2022b). Dictyocheirospora appendiculata differs from D. suae in that the appendages of conidia are located in the apex to middle, and each conidial row with less cells (9–11 vs. 12–15) (Shen et al. 2022b).
Figure 1 – Dictyocheirospora appendiculata (HKAS 131353, holotype). a Colony on the substratum. b Squash mount of conidioma. c, d, m Conidiogenous cells with conidia. e–l, n, o Conidia. p Germinating conidium. q, r Colonies on PDA from the surface and reverse. Scale bars: b = 30 µm, c, f, g = 10 µm, d, e, j–p = 20 µm, h, i = 15 µm.
Figure 8 – RAxML tree based on analysis of Dictyosporiaceae that combined ITS, LSU, and tef1-α dataset. The combined analyses include 81 strains with 2181 characters, including gaps (ITS: 498 bp, LSU: 814 bp, and tef1-α: 869 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 Murilentithecium clematidis (MFLUCC 14–0561 and MFLUCC 14– 6545 0562). The new collections are indicated in red. Ex-type strains are indicated with “T” after the strain number.