A new cryptic species of Pseudopestalotiopsis from Taiwan Author Ariyawansa, Hiran A. Department of Plant Pathology and Microbiology, College of Bio-Resources and Agriculture, National Taiwan University, Taiwan. Author Tsai, Ichen Department of Plant Pathology and Microbiology, College of Bio-Resources and Agriculture, National Taiwan University, Taiwan. Author Gareth Jones, E. B. Nantgaredig, 33 B St. Edwards Road, Southsea, PO 5 3 DH, Hants, UK text Phytotaxa 2018 2018-06-22 357 2 133 140 http://dx.doi.org/10.11646/phytotaxa.357.2.6 journal article 302404 10.11646/phytotaxa.357.2.6 afa3a8d0-4f42-4979-9166-251dde88d420 1179-3163 13705959 Pseudopestalotiopsis hydeae Ariyawansa & I. Tsai. , sp. nov. Index Fungorum number: IF= IF554119, FIGURE 2 . (a–j) Holotype : NTUH 17 - 003.1 . Etymology: Named after the British mycologist, Kevin D. Hyde, in recognition of his significant contributions towards the taxonomy of Pestalotiopsis . Description: Endophytic or saprobic on leaves of Diospyros sp. ( FIGURE 2. a–j ). Sexual morph : undetermined. Asexual morph : Conidiomata semi-immersed on host substrate; globose to oblate on PDA , black, 380–500 μm diam on PNA, globose, black and superficial on pine needle-substrate. Conidiophores indistinct, reduced to conidiogenous cells. Conidiogenous cells discrete, clavate, lageniform, ampulliform, cylindrical to subcylindrical, hyaline, rugose, straight to slightly curved, proliferating 2–5 times percurrently, 10–14 × 3–6 μm, x = 11 × 4 μm. Conidia ellipsoid, fusoid to subcylindrical, straight, sparsely curved, 4-septate, slightly constricted at septa, 23–29 × 5–7 μm, x = 27 × 6 μm; basal cell obconic with a truncate base, or acute, cylindrical to subcylindrical, hyaline and thin-walled, 4–6 μm long, x = 5 μm; three median cells 14–19 μm long, x = 17 μm (second cell from the base 5–7 μm long, x = 6 μm; third cell 4–6 μm long, x = 5 μm; fourth cell 5–6 μm long, x = 6 μm), doliiform, concolourous, brown to pale brown, septa darker than the cells; apical cell 3–6 μm long, x = 5 μm, hyaline, conic, cylindrical to subcylindrical, with 2–3 tubular apical appendages (mostly 3) arising from the apical crest, filiform, knobbed, 9–25 μm long, x = 18 μm; basal appendage single, tubular, unbranched, centric or excentric, knobbed, 5–8 μm long, x = 7 μm. Culture characteristics: Colonies whitish, with concentric ring-pattern and black conidiomata; reverse similar colour. Material examined : Taiwan , Nantou County , Huisun forest recreation area, on leaf of Diospyros sp. ( Ebenaceae ) 7 September 2017 , Ichen Tsai, HS12.1 ( holotype NTUH 17-003.1!)—extype living culture ( NTUCC 17-003.1); Taiwan , Nantou County , Huisun forest recreation area, on leaf of Diospyros sp. ( Ebenaceae ) 7 September 2017 , Ichen Tsai, HS12.2 ( paratype NTUH 17-003.2!)—extype living culture ( NTUCC 17-003.2). Taiwan , Nantou County , Huisun forest recreation area, on leaf of Diospyros sp. ( Ebenaceae ) 30 November 2017 , H . A . Ariyawansa, HS12.3 ( paratype NTUH 17-003.3!)—extype living culture ( NTUCC 17-001.3). Notes : Pseudopestalotiopsis hydeae is established here considering both morphology and phylogeny. Pseudopestalotiopsis hydeae is typical of Pseudopestalotiopsis in having dark concolourous median cells with knobbed apical appendages ( Maharachchikumbura et al. 2016 , Chen et al. 2018 ). Morphologically Ps. hydeae is similar to Ps. camelliae-sinensis , but differs in its comparatively smaller conidia (27 × 6 μm versus 29 × 8 μm), shorter apical appendages (9–25 μm versus 24–50 μm), smaller basal appendages (5–8 μm versus 5–10 μm) and the host ( Diospyros versus Camellia ) ( Chen et al. 2018 ).