Pseudofomitopsis fusca R. Saha, A. K. Dutta & K. Acharya 2024, sp. nov.
Creators: name: Saha, Rituparna
name: Dutta, Arun Kumar
name: Roy, Anirban
name: Acharya, Krishnendu
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Fungi
Basidiomycota
Agaricomycetes
Polyporales
Fomitopsidaceae
Pseudofomitopsis
Pseudofomitopsis fusca

description: Pseudofomitopsis fusca R.Saha, A.K.Dutta & K.Acharya sp. nov.
MycoBank: MB 848689
Figs 2–3
Diagnosis
Pseudofomitopsis fusca sp. nov. differs from Pseudofomitopsis microcarpa in having annual, pileate, glabrous, corky, straw yellow to honey yellow coloured, laterally stipitate to sub-stipitate basidiocarp, turning reddish brown to black towards base, 7–8 pores per mm, and cylindrical to oblong ellipsoid basidiospores that are non-reactive in cotton blue (CB).
Etymology
The epithet ‘fusca’ refers to the colour of the pileus upper surface.
Type material
Holotype INDIA – West Bengal • Jalpaiguri district, Samsing forest, near Gorumara National Park; 26°84′82″ N, 88°60′22″ E; 102 m a.s.l.; 4 May 2018; R. Saha, J. Tamang & K. Acharya RJK –01/2021; on dead wood of an unidentified angiosperm; GenBank no.: OQ918741 (ITS); CUH [AM776].
Paratype INDIA – West Bengal • Jalpaiguri district, Samsing forest, near Gorumara National Park; 26°84′82″ N, 88°60′22″ E; 914 m a.s.l.; 4 May 2018; R. Saha, J. Tamang & K. Acharya RJK –09/2021; on dead wood of an unidentified angiosperm; GenBank no.: OQ918742 (ITS); CUH [AM777].
Description
Basidiocarp pileate, perennial, triquetrous to ungulate, sessile, woody, hard, 20–35 mm wide, projecting 15–25 mm and 8–15 mm thick. Pileus upper surface applanate, shiny, glabrous, azonate, dark brown (9F4). Context 4–10 mm thick, brownish grey (7C2), woody, unchanged in KOH. Margin concolorous to the pileus upper surface, 0.8–1.5 mm thick. Pore surface yellowish grey (2C2), pores angular, 3–5 per mm. Tubes concolorous to the pore surface, 2–5 mm deep.
Hyphal system dimitic. Generative hyphae hyaline, thin-walled, branched, clamped, 1.65–3.5 µm wide. Skeletal hyphae thick-walled to solid, highly branched, hyaline, 1.5–5 µm wide. Basidia clavate, 4-sterigmate, hyaline, smooth, thin walled, 10–20 × 3.5–5.5 µm in diam. Cystidia absent. Cystidioles fusoid, thin-walled, hyaline, smooth, 9.5–16.5 × 3–3.5 µm in diam. Basidiospores thin-walled, hyaline, smooth, ellipsoid, aguttulate, reacting positive in cotton blue (CB), 3–3.7–5 × 1.5–2.9–3.5 µm in diam., Q = 1.09–1.99, Q m = 1.34.
Remarks
The new species is quite exceptional. Characteristic features of Pseudofomitopsis fusca sp. nov. are: perennial, triquetrous to ungulate, sessile (20–30 × 15–20 × 8–15 mm) basidiocarp with glabrous, dark brown upper surface; yellowish grey pore surface; dimitic type of hyphal system with clamped generative hyphae; fusoid cystidioles; ellipsoid, CB positive basidiospores measuring 3–5 × 1.5–3.5 µm with a mean Q value of 1.34.
description: Published as part of Saha, Rituparna, Dutta, Arun Kumar, Roy, Anirban & Acharya, Krishnendu, 2024, Two new polyporoid species of Fomitopsidaceae (Polyporales, Basidiomycota) from India, pp. 122-136 in European Journal of Taxonomy 935 on pages 128-129, DOI: 10.5852/ejt.2024.935.2551, http://zenodo.org/record/11353417