Neodeightonia septata N. Wu, A.J. Dissanayake & Jian K. Liu, 2022

Wu, Na, Dissanayake, Asha J., Chethana, K. W. Thilini & Liu, Jian-Kui, 2022, Neodeightonia septata sp. nov. and N. subglobosa (Botryosphaeriaceae) from northern Thailand, Phytotaxa 575 (2), pp. 129-139 : 133-135

Neodeightonia septata N. Wu, A.J. Dissanayake & Jian K. Liu sp. nov. Fig. 2

MycoBank number: MB 844409, Facesoffungi number: FoF010671.

Etymology: —The specific epithet “septata” refers to the septum observed in mature conidia.

Holotype: — MFLU 22-0003 .

Saprobic on a dead culm of palm, as raised black spots on the host surface. Sexual morph: not observed. Asexual morph: Conidiomata 80–135 μm diam., 50–105 μm high (n = 20), superficial or semi-immersed in the substrate, unilocular to multilocular, solitary or aggregated, cylindrical or subglobose, dark brown to black. Peridium up to 10–21 μm wide, composed of dark brown, thick-walled, textura angularis cells, becoming thin-walled and hyaline towards the inner region. Ostiole 25–30 μm diam., cylindrical, straight or curved, centrally or laterally located. Paraphyses absent. Conidiophores reduced to conidiogenous cells. Conidiogenous cells 4–8 μm long, 3–5 μm wide (n = 20), cylindrical, hyaline, straight to curved, smooth-walled. Conidia (13.5–)15–19(–21) × (6–)8–9(–12) μm (x = 17 × 9 μm, n = 50), ellipsoidal to obovoid, rounded at the apex, frequently constricted in the middle, initially hyaline, aseptate, guttulate, without mucilaginous sheath, becoming pale to dark brown when mature, granulate, forming a septum.

Culture characteristics: —Conidia germinating on PDA within 12 h. Colonies reaching 90 mm diam. after 4–5 days at 20–23 °C, circular, white during the first few days, sparse, aerial, surface smooth with crenate edge, filamentous, after 2 weeks becoming dark brown to black.

Material examined: — THAILAND. Chiang Rai: Thoeng, Tambon Nang Lae, Rai Ruen Rom Organic Farm , 19°39’30.2’’N, 100°09’26.4’’E, on a dead palm culm, 11 June 2019, Na Wu, YW 86 ( MFLU 22-0003 , holotype), extype living culture MFLUCC 22-0004 ; ibid., ( GZAAS 22-0068 , isotype), living culture GZCC 22-0067 .

Notes: —The phylogenetic result showed that the two isolates of Neodeightonia septata clustered together and formed a distinct lineage with absolute bootstrap support. It is phylogenetically close to N. rattanica and N. rattanicola but is represented as a distinct species. In addition, N. septata is morphologically distinguished from the abovementioned species by having 1-septate conidia, while no septum was observed in N. rattanica nor in N. rattanicola ( Table 2 ).

Figures

FIGURE 2. Neodeightonia septata (MFLU 22-0003, holotype). a. Substrate with conidiomata. b, c. Appearance of black conidiomata on palm culm. d. Vertical section of conidiomata. e. Section of peridium. f. Ostiolar region. g–i. Conidiogenous cells and developing conidia. j–m. Hyaline, aseptate immature conidia.n. Brown, 1-septate mature conidia. o. Germinating conidium.p, q. Colonies after 7 days on PDA (p from above, q from below). Scale bars: b = 50 μm, c = 10 μm, d–f = 20 μm, g–o = 5 μm.