Neosulcatispora agavicola L. S. Dissan., Wanas., Phookamsak & J. C. Xu 2026, sp. nov.

Neosulcatispora agavicola L. S. Dissan., Wanas., Phookamsak & J. C. Xu sp. nov. Fig. 2 Etymology. The epithet refers to the host genus Agave, from which the fungus was isolated. Holotype. KUN- HKAS 155191. Description. Saprobic on dry leaves of Agave vera-cruz (Asparagaceae). Sexual morph: Undetermined. Asexual morph: Coelomycetous. Conidiomata 250–300 × 180–220 μm (x ̄ = 265.87 × 199.06 μm, n = 10), semi-immersed to erumpent through host epidermis, solitary, becoming aggregated, globose, glabrous, uni-loculate, with ostiolate, visible as dark brown dots on host surface. Ostiole central, minutely papillate, with pore-like opening, protruding through host surface. Conidiomata wall 30–50 μm (x ̄ = 42.76 μm, n = 10) wide, comprising 3–4 layers of small, flattened, dark brown to black, pseudoparenchymatous cells, of textura angularis to textura prismatica, slightly paler towards the inner layer, outer layers composed of thick-walled, coriaceous, inner layers composed of flattened, thin-walled cells. Conidiophores reduced to conidiogenous cells; or with a supporting cell, lining the inner cavity, hyaline. Conidiogenous cells lining the inner cavity of the conidiomata, hyaline, smooth-walled, thin-walled, aseptate, ampulliform to lageniform or subcylindrical; some phialidic, with inconspicuous periclinal thickening, while others show tightly aggregated percurrent proliferations at the apex, producing conidia singly. Conidia 7–10.5 × 4–6 μm (x ̄ = 7.97 × 4.89 μm, n = 50), solitary, varied in shape, ellipsoidal to subfusoid, or oblong, with obtuse or acute ends, straight to irregularly curved, initially hyaline, with two big polar guttules, becoming golden to brown, 1 - euseptate, upper cell slightly shorter and wider than the lower cell, thick- and rough-walled, prominently striate, with striations covering the length of the conidium, becoming dark brown after discharge. Culture characteristics. Colony grows faster on PDA, reaching 20 mm in diameter after seven days at 25 ° C under dark conditions, flat, spreading, with moderate aerial mycelium and margin irregular, producing brown-black pigment when mature. Sporulated after 30 days. In vitro: Stromatic 1240 × 1325 μm, immersed to semi-immersed on PDA, solitary or aggregated, with or without an ostiole, visible as dark brown to black dots. Conidiomata wall comprising brown cells of textura angularis. Conidiophores reduced to conidiogenous cells. Conidiogenous cells lining the inner cavity of the conidiomata, hyaline, smooth-walled, thin-walled, aseptate, ampulliform to lageniform or subcylindrical; some phialidic, with inconspicuous periclinal thickening, while others show tightly aggregated percurrent proliferations at the apex, producing conidia singly. Conidia 7.43–11.10 × 3.49–4.83 μm (x ̄ = 9.02 × 4.16 μm, n = 40), solitary, subcylindrical, straight or slightly curved, initially hyaline, becoming 1 - septate, brown, prominently striate, with striations covering the length of the conidium. Materials examined. China • Yunnan, Honghe Hani and Yi Autonomous Prefecture, Honghe County, 23.2452°N, 102.1546°E, 762 m, on dry leaves of Agave vera-cruz (Asparagaceae), 14 January 2026, L. S. Dissanayake, HS 2 A 1 A (holotype, KUN- HKAS 155191), ex-type culture, KUNCC 25-21586; • ibid., HS 2 A 1 B (isotype, KUN- HKAS 155192), ex-isotype culture, KUNCC 25-21587, HS 2 A 1 C (KUN- HKAS 155193), living culture, KUNCC 25-21588. Note. The three isolates representing Neosulcatispora agavicola form a fully supported, independent lineage (100 % MLBS, 1.00 BYPP; Fig. 1) within Neosulcatispora sensu stricto. The species can be distinguished from N. hongheensis by its larger conidiomata and 1 - septate mature conidia. It is morphologically similar to N. agaves, which produces prominently longitudinally striate, 1 - septate conidia measuring (7 –) 9–11 (– 12) × (3.5 –) 4 (– 4.5) μm (Table 2). Because the conidial dimensions of the two species overlap substantially, the distinction of N. agavicola from N. agaves cannot be based on morphology alone. Although the conidiomata of N. agavicola are slightly smaller than the maximum diameter of approximately 300 μm reported for N. agaves (Table 2), this difference is insufficient by itself to justify species delimitation. Neosulcatispora agavicola and N. agaves are not recovered as immediate sister taxa in the combined phylogeny (Fig. 1). Pairwise nucleotide comparisons between N. agavicola and N. agaves revealed no differences in LSU (0 / 846 bp). Across 540 ITS positions, 12 nucleotide differences were detected when gap-containing positions were excluded (2.22 %), whereas 23 positions differed when gaps were counted as differences (4.26 %). Consistent with these differences, the ITS - based phylogeny recovered the three isolates of N. agavicola as a distinct monophyletic lineage with 94.9 % SH-aLRT and 100 % ultrafast bootstrap support, separate from N. hongheensis and N. agaves (Suppl. material 1). SSU, tef 1 - α and rpb 2 sequences are unavailable for N. agaves preventing direct comparisons using these loci. The new species are in bold. In comparison with Neosulcatispora hongheensis, N. agavicola differs by 2 / 846 bp in LSU (0.24 % difference), 20 / 540 bp in ITS (3.7 % difference), 25 / 873 bp in tef 1 (2.86 % difference) and 46 / 891 bp in rpb 2 (5.16 % difference). These molecular differences, together with the clear differences in conidiomatal size and conidial septation, support the recognition of N. agavicola and N. hongheensis as distinct species.