Distoseptispora dipterocarpi N. Afshari & K.D. Hyde, sp.nov

MycoBank number: MB 558392; Index Fungorum number: IF 558392; Facesoffungi number: FoF 13099. Fig. 1.

Etymology: the epithet refers to the host genus, Dipterocarpus.

Holotype: MFLU 22-0151

Saprobic on woody litter of Dipterocarpus sp. Sexual morph: Undetermined. Asexual morph: Hyphomycetous. Colonies on the substratum superficial, effuse, gregarious, hairy, erect, dark brown to black. Mycelium superficial on host substrate, composed of septa, branched, dark brown, thick-walled hyphae. Conidiophores 14–72 × 5–7 μm (x̄ = 32.5 × 6 μm, n = 20), macronematous, mononematous, erect or flexuous, septate (1-7), branched, single or in groups, brown, thick-walled, robust at the base. Conidiogenous cells 4–13.5 × 4–6.5 μm (x̄ = 8 × 5 μm, n = 20), monoblastic, terminal, determinate, cylindrical, brown. Conidia 31.5–350 × 6.5–12 μm (x̄ = 146 × 9 μm, n = 20), solitary, cylindrical or obclavate, elongated, straight or slightly curved, truncate at the base, rounded at the apex, 10–72 distoseptate, smooth, olivaceous when young, brown tinge when mature, mostly lighter towards the apex, thick-walled, and scars or pigmented disjunction present in the attachment site.

Culture characteristics: Colonies on PDA, circular, reaching 10 mm diam. at 7 days at 25 °C. Cultures from above hazel, dense mycelium, circular, surface smooth, dry, fluffy, undulate at the edge; reverse black at the center, radiating black outwardly.

Material examined: Thailand, Chiang Rai Province, on woody litter of Dipterocarpus sp. 27 September 2021, Naghmeh Afshari, S6NAD2 (MFLU 22-0151, holotype); ex-type living culture MFLUCC 22-0104.

GenBank accession numbers: LSU: OP600052; ITS: OP600053; rpb2: OP595140.

Fig. 3. Distoseptispora dipterocarpi. a, b Colonies on Dipterocarpus sp. woody litter. c conidiophore. d,e conidiophores with conidia. f-j Conidia k Germinated spore. l, m Colony on PDA (front, reverse). Scale bars: a,b, e–h = 100 μm, k= 50 μm, c,d,i,j = 20 μm.

Fig. 1. Consensus RAxML generated from combined LSU, ITS, and rpb2 sequence data. Bootstrap support values ≥ 60% and Bayesian posterior probabilities ≥ 0.95 are shown near the branches. The tree is rooted with Aquapteridospora aquatic (MFLUCC 17-2371) and A. fusiformis (MFLU 18-1601). The new taxon (MFLUCC 22-0104) is indicated in bold and blue. Type species are in bold.