Distoseptispora iloiloensis Bagacay, Candole, E. B. G. Jones & M. S. Calabon 2026, sp. nov.

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Distoseptispora iloiloensis Bagacay, Candole, E. B. G. Jones & M. S. Calabon sp. nov. Fig. 3 Etymology. Named after Iloilo Province, Philippines, where the fungus was first observed. Holotype. UPVMI 25–0024. Description. Saprobic on submerged decaying wood in freshwater habitat. Sexual morph: Undetermined. Asexual morph: Colonies superficial, effuse, gregarious, brown or dark brown, hairy. Mycelium mostly immersed, composed of branched, septate, smooth, pale brown to brown hyphae. Conidiophores 14–34 × 4–8 μm (x ¯ = 25.1 × 6.3 μm, n = 10), macronematous, mononematous, brown to dark brown, solitary, 2–4 - septate, erect, straight or flexuous, unbranched, single or in groups of 2 or 3, smooth, cylindrical, truncate at the apex, slightly constricted at septa. Conidiogenous cells holoblastic, monoblastic, integrated, terminal, determinate, smooth, cylindrical. Conidia (82 –) 102–200 (– 385) × 6–19 µm (x ¯ = 158.4 × 13.7 µm, n = 25) acrogenous, solitary, dry, obclavate, cylindrical or rostrate, elongated, smooth-walled, straight or slightly curved, up to 39 - distoseptate, guttulate, olivaceous to dark brown, mostly slightly constricted at septa, tapering towards the rounded apex, truncate at the base. Conidial secession schizolytic. Culture characteristics. Conidia germinated on potato dextrose agar and produced germ tubes within 24 h. Colonies grown on PDA, circular, mycelium flat, dense, reaching 25–30 mm diam. after 30 days of incubation at 25 ° C, grey or brown, reverse-side dark brown. Material examined. Philippines, Iloilo, Miagao, Tinagong Dagat Lake, on submerged wood from a stream, 23 September 2023, Gerlie Mae Candole, TGFW 12 (UPVMI 25–0024), living culture UPVMICC 25–0024. GenBank accession numbers. ITS = PZ 203857, LSU = PZ 208527, TEF 1 - α = PZ 221697 Notes. Distoseptispora iloiloensis forms a well-supported clade with D. daanyuanensis (SAUCC 12326-1, SAUCC 12326-2), based on combined ITS – LSU – RPB 2 - TEF 1 - α sequence data (100 % MLBS, 1.00 BYPP; Fig. 1). Both taxa conform to the generic circumscription of Distoseptispora in producing holoblastic, monoblastic, acrogenous conidiogenous cells and distoseptate, obclavate to rostrate conidia. Morphologically, the two species are readily separable by conidial dimensions and septation patterns. Distoseptispora daanyuanensis is characterised by exceptionally long and highly septate conidia (23.1–696.2 × 9.3–17.9 μm; 4–92 distosepta), representing the broadest range in both size and septation (Liu et al. 2025). In contrast, D. iloiloensis is distinguished by comparatively smaller conidia ((82 –) 102–200 (– 385) × 6–19 μm) with up to 39 distosepta, generally lacking apical percurrent regeneration. Pairwise nucleotide comparisons further support their distinction wherein D. iloiloensis differs from D. daanyuanensis by 1.40 % (8 / 573 bp, ITS), 1.78 % (15 / 843 bp, LSU) and 0.78 % (7 / 892 bp, TEF 1 - α) sequence divergence. Ecologically, the taxa occupy discrete substrates: D. daanyuanensis is reported from decaying wood in peat swamp forest and D. iloiloensis from submerged wood in freshwater habitat (Liu et al. 2025). This ecological segregation, coupled with subtle, yet stable morphological differences, suggests niche specialisation within this phylogenetically cohesive lineage.