Pseudoconiocessia L. Lu & Tibpromma

Lu, Li, Karunarathna, Samantha C., Liu, Yina, Elgorban, Abdallah M., Tibpromma, Saowaluck & Jayawardena, Ruvishika S., 2024, Pseudoconiocessia xishuangbannaensis gen. et sp. nov. in Coniocessiaceae, Xylariales from Coffea liberica in China, Phytotaxa 641 (2), pp. 125-137 : 130

Pseudoconiocessia L. Lu & Tibpromma , gen. nov.

Index Fungorum number: IF 901343, Facesoffungi number: FoF 15057

Type species: Pseudoconiocessia xishuangbannaensis L. Lu & Tibpromma

Etymology:— Named after its morphological similarity to Coniocessia .

Saprobic on dead or decaying plants. Sexual morph: Ascomata carbonaceous, some erumpent above the host surface, solitary or scattered, semi-immersed to immersed beneath the clypeus, visible as black patches, sub-globose to globose in shape, uni-loculate, cone-shaped, with ostiole at central, shiny black, periphasate ostiolar canal. Peridium brown to blackish brown, composed of cells of textura angularis. Hamathecium numerous, asepate, branched, flexuous, paraphyses. Asci 4–8-spored, unitunicate, cylindrical, hyaline, with furcate pedicel, with apical ring, J+ in Melzer’s reagent. Ascospores uniseriate, yellowish to brown, fusiform or ellipsoid, straight, guttulate, conical at the lower end, aseptate, germ slit present when mature, without a sheath. Asexual morph: Not observed.

Notes:— Based on phylogenetic analyses, our strains clustered within Coniocessiaceae and formed an independent lineage well separated from Coniocessia and Paraxylaria with 73% ML, 0.92 PP statistical support ( Fig. 1 ). However, Pseudoconiocessia can be distinguished from Coniocessia and Paraxylaria by aseptate hamathecium, 4–8-spored asci with flat apical ring, and fusiform ascospores, conical at lower end ( Asgari & Zare 2011, Wanasinghe et al. 2018, Samarakoon et al. 2022). Coniocessia consists of five species that are reported as epiphytic fungi with sexual morphs, some with nodulisporium-like anamorphs, while Coniocessia is different from Pseudoconiocessia by having 4-spored asci without apical structures, and with a distinct germ-slit extending over the whole length of the ascospores ( Asgari & Zare 2011), whereas Paraxylaria contains only two species and they were discovered as saprobic fungi with sexual morphs; it can be distinguished from Pseudoconiocessia by ascospores that lack germ slits ( Wanasinghe et al. 2018, Samarakoon et al. 2022). Additionally, our new taxon shares similar morphology to the generic concept of Coniocessiaceae in having immersed ascomata with ostiole, and unitunicate asci with brown and ellipsoidal or fusiform ascospores ( Asgari & Zare 2011, Wanasinghe et al. 2018, Samarakoon et al. 2022). Therefore, Pseudoconiocessia is introduced here as a new genus in Coniocessiaceae , with P. xishuangbannaensis as the type species, isolated from decaying twigs of Liberian coffee plants in China.

Figures

FIGURE 1. RAxML tree based on a combined dataset of ITS, LSU, and RPB2 gene sequences. Bootstrap support values for ML equal to or greater than 70% and PP equal to or greater than 0.90 are given above the nodes. Strains of the newly described species are in red, while all the type strains are in bold.