Periconia motuoensis B.B. Sun, S.C. He & Q. Zhao, 2025

Sun, Bing-Bing, He, Shu-Cheng, Yu, Feng-Ming, Li, Cui-Jin-Yi, Yang, Yan-Yan, Wang, Jian-Rui & Zhao, Qi, 2025, A new species of Periconia (Periconiaceae, Pleosporales) from Xizang, China, Phytotaxa 693 (2), pp. 133-145 : 138-139

Periconia motuoensis B.B. Sun, S.C. He & Q. Zhao , sp. nov. Fig. 2 .

Index Fungorum number: IF902655; Facesoffungi number: FoF 16560

Etymology: The specific epithet refers to the locality “Motuo” from where the holotype was collected.

Saprobic on dead sheaths of Poaceae . Sexual morph: Undetermined. Asexual morph: Hyphomycetous. Colonies numerous on substrate, dark brown to black, hairy. Conidiophores 430−600 μm × 13−21 μm (x̅ = 520 × 16 μm, n = 20), macronematous, mononematous, erect, straight or flexuous, branched at the apex, smooth, thick-walled, solitary, septate, brown to black. Conidiogenous cells polyblastic, integrated, terminal, subglobose, smooth to verruculose, brown. Conidia 21−26 μm × 10−14 μm (x̅ = 24 × 12 μm, n = 30), acrogenous, ellipsoidal to cylindrical, verrucose, with two guttulates when mature, thick- and rough-walled, sometimes septate, pale brown to brown.

Culture characteristics: Conidia germinated on PDA within 24 hours, and produced one or two germ tubes. After three weeks at 25℃, the colony diameter reached about 8 cm with white edges and a grey center, appearing round, flocculent, and with sparsely hairy edges. The reverse of the colony was grey with white edges.

Material examined: CHINA, Xizang, Linzhi, Motuo , on dead sheaths of Poaceae , 12 July 2022, coll. Yan-Yan Yang, YYY319 (HKAS 135698, holotype), ex-type culture KUNCC24-17924 ; ibid., YYY319-2 (HKAS 135699, isotype), living culture KUNCC24-17925 ; ibid, 9 August 2023, coll. Shucheng He, SBB39 (HKAS 134948), living culture KUNCC24-17926 ; ibid., SBB39A (HKAS 134949), living culture KUNCC24-17927 .

Notes: Periconia motuoensis clustered with P. imperatae , P. spodiopogonis and P. submersa in the phylogenetic tree with high supports (ML / PP = 77% / 1.00) ( Fig. 1 ). Based on the analyses of molecular data, P. motuoensis differs from P. spodiopogonis by 2.65 % in ITS, 0.12 % in LSU, no difference in SSU, and 1.25 % in tef1, and it differs from P. imperatae by 2.62 % in ITS, 0.13 % in LSU, no difference in SSU, and 1.11 % in tef1; as well as it differs from P. submersa by 3.01 % in ITS, 0.02 % in LSU, no difference in SSU and 1.12 % in tef1. Morphologically, the conidia of P. motuoenis are similar to P. aquatica , P. imperatae , and P. spodiopogonis , all of which are nearly ellipsoidal. However, the conidia of P. motuoensis are significantly larger than the ones of P. imperatae and P. aquatica (21−26 μm × 10−14 μm vs. 8.5−13.5 × 5.5−8.5 μm and 10−12 × 6−7 μm respectively). Compared with P. spodiopogonis , the conidia of P. motuoensis are slightly constricted in the middle, longer (21−26 × 10−14 μm vs. 14.5−24.5 × 9.5−15.5 μm), and have two obvious guttulates when mature. In addition, five species, viz., P. chandoliensis , P. guangdongensis , P. notabilis , P. palmivora , and P. pergularigena , lack molecular information, and they can be easily separated from P. motuoenis because of their spherical or nearly spherical conidia.

Figures

FIGURE 1. Phylogram generated from ML analysis based on concatenated ITS, LSU, SSU, and tef1 datasets.The scale bar indicates 0.02 changes per site. ML bootstrap proportions equal to or greater than 70% and BIPP equal to or greater than 0.90 are shown on the nodes. The type strains are in bold, and the newly generated sequences are indicated in red.

FIGURE 2. Periconia motuoensis (HKAS 135698, holotype). a Host substrate. b Colonies on the natural substrate. c–e Conidiophores. f–h Conidial heads bearing conidiogenous cells and conidia. i–l Conidia. m Germinating conidia. n–o Colonies grown on PDA for 15 days from above and below. Scale bars: c–e = 200 μm, f–h = 50 μm, i–m = 20 μm.