Veronaea polyconidia P.W. Su, Y.P. Chen & Maharachch., 2023

Su, Pengwei, Chen, Yanpeng, Syed, Asad, Bahkali, Ali H. & Maharachchikumbura, Sajeewa S. N., 2023, Taxonomic novelty in Sichuan Province, China: Veronaea polyconidia sp. nov. (Herpotrichiellaceae), a new addition to hyphomycetous fungi, Phytotaxa 632 (2), pp. 118-130 : 125

Veronaea polyconidia P.W. Su, Y.P. Chen & Maharachch. sp. nov. ( FIGURE 2 ) MycoBank: MB 851066

Etymology: Referring to the prolific production of conidia.

Holotype: HKAS 130506

Saprobic on a decaying branch of an unidentified Betulaceae plant. Asexual morph: Hyphomycetous. Colonies on the natural substrate numerous, spreading very widely, effuse, dark brown to black, and hairy. Conidiophores 1125– 1515 μm long (x = 1340, n = 20), 45–70 μm wide (x = 60 μm, n = 20), macronematous, mononematous, straight or slightly flexuous, unbranched, solitary, cylindrical, rough-walled, thick-walled, brown to dark brown. Conidiogenous cells are polyblastic, terminal, cylindrical, rachis with crowded, flat to slightly prominent, pale brown, fertile parts subhyaline. Conidia 11–16 × 3–5 μm (x = 14 × 4 μm, n = 40), solitary and smooth, cylindrical to pyriform, rounded at apex and truncate at base, pale brown, 1–3-septate (mostly 3), often constricted and medium brown at septa. Sexual morph: Undetermined.

Culture characters: Colonies on PDA reached 37 mm diam after 20 days at 25 °C in the dark, blackish green at the margin, dark brown at the middle, sparse to medium dense, surface rough, woolly at the margin; dark brown to black in reverse.

Materials examined: CHINA, Sichuan Province, Chongzhou City, Baiyungou , 30°47′35′′ N, 103°23′49′′ E, elevation 990 m, on decaying branch of an unidentified Betulaceae , 27 September 2021, YP Chen BY 97 (HKAS 130506, holotype), ex-type culture CGMCC 3.25589 = UESTCC 23.0137 ; ibid., BY110.1 (HUEST 23.0138), living culture UESTCC 23.0138 ; ibid., Pengzhou City, Huilonggou , 31°18′11′′ N, 103°45′35′′ E, elevation 1400 m, on a decaying branch of an unidentified Betulaceae plant, 28 July 2021, YP Chen HLG97 (HUEST 23.0139), living culture UESTCC 23.0139 .

Notes: The phylogenetic tree showed that our three new isolates formed a distinct clade sister to the isolates of V. botryosa , including the ex-type strain CBS 254.57 ( FIGURE 1 ). The BLASTn analysis of V. botryosa (CBS 254.57) and Veronaea polyconidia (CGMCC 3.25589) shows 92% identity (590/638, 18 gaps) using ITS. Veronaea botryosa was isolated from Sansa olive slag in Pisa, Tuscany, Italy, in 1954, as per the description by Ciferri and Montemartini (1957). Our collections have similar morphological characteristics in the shape of conidia with the V. botryosa ( Ciferri & Montemartini 1957, Dong et al. 2018, Yang et al. 2023). However, V. polyconidia differs from V. botryosa in having relatively larger conidia (11–16 × 3–5 μm vs. 5–12 × 3–4 μm) and longer conidiophores (1125–1515 μm vs. up to 250 μm) ( Ciferri & Montemartini 1957). Based on morphological diagnosis and phylogenetic analyses, we describe our new collections as Veronaea polyconidia .

Figures

FIGURE 1. Phylogram of the best-scoring ML consensus tree. Novel isolates and synonymized taxa are indicated in blue. Isolates from type materials are in bold. The ML ultrafast bootstrap values/Bayesian PP greater than 95%/0.95 are shown at the respective nodes. The tree is rooted with Cyphellophora oxyspora CBS 698.73 (Cyphellophoraceae, Chaetothyriales).

FIGURE 2. Veronaea polyconidia (HKAS 130506, holotype). a–c Colonies on the natural substrate d Conidiophores with spherical conidial heads e Apical conidia f Conidiophores g Conidiogenous cells and conidia h Conidia; i–l From the PDA medium, i Conidiophores and conidiogenous cells j,k conidiogenous cells with attached conidia l Conidia m, n Colony on PDA from above and below. Scale bars: d 200 μm; e, f 100 μm; g–l 20 μm.