Phyllosticta capitalensis Henn., Hedwigia 48: 13 (1908) [1909]

Index Fungorum number: IF168326; Fig. 1, 2

Endophytic in the leaves of Dendrobium chrysanthum. Asexual morph: (on PDA) vegetative hyphae 0.8–2.1 μm diameter, hyaline, septate, branched, smooth. Conidiomata scattered around colony surface, aggregate, globose to irregular, greenish black. Conidiophores 4–52.5 μm long, cylindrical, straight to flexuous, hyaline, septate. Conidiogenous cells holoblastic. Conidia (6–) 6.5–7 (–8) × (3–) 3.5–4 (–4.5) μm (x̄ = 6.6±0.6 × 3.6±0.3 μm, n = 20), ellipsoidal, hyaline, guttulate, sometimes slightly curved, solitary, smooth-walled. Sexual morph: (on WA of a slide culture) vegetative mycelia 1.7–4.4 μm diameter, brown, curved, septate, swollen at nodes. Ascomata protrude from the suface of media, clavate to cylindrical, black, independent. Asci (45–) 50–61 (–62) × (7.5–) 8–8.5 (–9) μm (x̄ = 54.8±6 × 8.1±0.5 μm, n = 12), unitunicate, mostly with 8 ascospores, cylindrical to clavate with obtusely rounded or slightly square at apex, hyaline, smooth-walled. Ascospores (7.5–) 8–9 (–10) × (3.5–) 4–4.5 (–5) μm (x̄ = 8.5±0.8 × 4.5±0.4 μm, n = 8), sub-globose to pyriform, two ends rounded or truncated, hyaline, widest in the middle or near the middle, guttulate, smooth-walled, listed interlaced.

Culture characteristics – Colony on PDA surface superficial, with flat margin, rough, grained, radiated, dense, jungle green front, reverse greenish black with a growth rate of 2.5 mm/day at 28 ℃.

Material examined – China, Guizhou Province, Xingyi City, orchid nursery, from leaves of Dendrobium chrysanthum, 16 October 2016, Bao-Wen Chen, living culture Strain2 died after sequencing; Thailand, Chiang Rai Province, Wat Phra That Doi Tung (Temple of Doi Tung Pagodas), from leaves of Dendrobium chrysanthum, 19 December 2013, Sureeporn Nontachaiyapoom, Natdanai Aewsakul, Xiao-Ya Ma, living cultures MFLUCC 14-0088.

GenBank submissions – ITS: MW084361 (MFLUCC 14-0088), MW084362 (Strain2); ACT: MW092167 (MFLUCC 14-0088), MW092168 (Strain2); TEF1-α =MW160396 (MFLUCC 14-0088), MW160397 (Strain2).

Known distribution (based on molecular data) – Worldwide (Okane et al. 2003, Glienke et al. 2011, Wikee et al. 2013a, Lin et al. 2017).

Known hosts (based on molecular data) – 70 plant families (Okane et al. 2003, Glienke et al. 2011, Wikee et al. 2013a, Lin et al. 2017).

Notes – Isolates MFLUCC 14-0088 and Strain2 have identical sequences, so we regard them as the same species. Both clustered with Phyllosticta capitalensis isolates together with its ex-type strain CBS 128856. There are only three base pair differences between MFLUCC 14-0088 and P. capitalensis CBS 128856. The asci of MFLUCC 14-0088 are bitunicate and smaller than that of other strains, and ascospores are also smaller. The conidia are shorter and wider than that of P. mangifera-indica (6–)9(–13) × (4–)5(–6) μm. No mucilaginous sheath was found around the conidia.

Fig. 1 – Asexual morph of Phyllosticta capitalensis (MFLUCC 14-0088, new host record). a–b Colony on PDA (a Surface, b Reverse). c–j Conidiophores with conidia. k–p Conidia. Scale bars: c–f = 10 μm, g–p = 5 μm.

Fig. 2 – Sexual morph of Phyllosticta capitalensis (MFLUCC 14-0088, new host record). a–b Colony on PDA (a Surface, b Reverse). c Fruiting body on WA slide culture. d Mycelia on slide culture. e–i Asci. j Ascospore. k Mycelium with nucleates. Scale bars: c = 500 μm, d–g = 10 μm, h–j = 5 μm, k = 10 μm.