Neomyrmecridium sichuanense Y.P. Chen & Maharachch., 2025

Chen, Yanpeng, Liao, Yuechi, Shami, Ashwag, Alharbi, Nada K., Liu, Jian-Kui & Maharachchikumbura, Sajeewa S. N., 2025, Advancements in fungal and fungi-like diversity with a new species and updated records, Phytotaxa 701 (2), pp. 127-147 : 134-135

Neomyrmecridium sichuanense Y.P. Chen & Maharachch. , sp. nov. ( FIGURE 3 )

Mycobank: MB 857089

Holotype: HUEST 24.0068

Etymology: The epithet refers to where the collection was made, Sichuan Province.

Saprobic on decaying twigs of an unidentified herbaceous plant. Sexual morph: Not observed. Asexual morph: Colonies on natural substrates effuse, scattered, or aggregated, hairy, brown, glistening. Conidiophores 93–130 × 4.0–5.0 (x = 115 × 4.5, n=20) macronematous, mononematous, erect, solitary or in small groups, lower part straight, upper part flexuous, cylindrical, reddish brown, slightly paler towards the apex, septate, unbranched. Conidiogenous cells polyblastic, integrated, terminal and intercalary, determinate, sympodial, denticulate, flexuous, cylindrical, pale reddish brown to subhyaline. Conidia acropleurogenous, solitary, fusiform or narrowly obovoid, subhyaline to pale brown, 0–1-septate, finely verrucose, 9.5–14.5 × 4.0–4.5 μm (x = 12 × 4.5 μm, n = 30).

Culture characteristics: Single-spore isolation was repeated three times on PDA and WA media, and no germinated spore was observed.

Material examined: CHINA. Sichuan Province, Chengdu City, Dujiangyan City, Longchi National Forest Park, 103°38’46 E, 31°0’11” N, elevation 702 m, on decaying branches of an unidentified herbaceous plant, 5 October 2021, Y.P. Chen and W.H. Tian, LC64 ( HUEST 24.0068, holotype)

Notes: Our fungus exhibits the typical characteristics of Neomyrmecridium ( Xu et al. 2023) . In the multi-gene phylogenetic tree ( FIGURE 1 ), specimen HUEST 24.0068 forms a distinct branch. Its ITS sequence shows the highest similarity to Neomyrmecridium sorbicola CBS 143433, but with only 91% sequence identity (510/559, 8 gaps). Morphologically, HUEST 24.0068 and Neomyrmecridium sorbicola exhibit a similar conidial size dimension (7–15 × 4–5 μm), but the latter is characterized by the possession of appendages, a feature absent in HUEST 24.0068 (Crous et al. 2018). Therefore, the study proposed that the newly collected specimen be a new species to Neomyrmecridium , which is designated N. sichuanense .

Figures

FIGURE 1. A phylogram of Neomyrmecridium and Myrmecridium species was generated from ML analyses based on a combined dataset of ITS and LSU sequence data. Ultrafast bootstrap values from ML and MP>=95 and posterior probability from Bayesian inference>=0.95 are shown above the nodes as ML/MP/BI. The new isolates are in red, and ex-type strains are in bold. The tree was rooted with Lanspora cylindrospora NFCCI 4391.

FIGURE 3. Neomyrmecridium sichuanense (HUEST24.0068,holotype).A.Natural substrates;B, C. Conidiophores;D–F.Conidiophores with apical developing conidia; G. Close-up of a conidiogenous cell; H–I. Conidia. Scale bar: C, D = 20 µm, E–I = 10 µm.