Colletotrichum tongrenense S.X. Zhou, J.C. Kang & K.D. Hyde

Zhou, Sixuan, Qiao, Lijun, Jayawardena, Ruvishika S., Hyde, Kevin D., Xiaoya Ma,, Wen, Tingchi & Kang, Jichuan, 2019, Two new endophytic Colletotrichum species from Nothapodytespittosporoides in China, MycoKeys 49, pp. 1-14 : 1

Colletotrichum tongrenense S.X. Zhou, J.C. Kang & K.D. Hyde sp. nov. Fig. 3

Etymology.

‘tongrenense’ referring Tongren City, site of collection of type species.

Description.

Endophytic in leaves and stems of Nothapodytes pittosporoides . Sexual morph: Undetermined. Asexual morph: On WA, vegetative hyphae 1.4-6 µm diam. (n=10), smooth-walled, septate, branched, hyaline. Chlamydospores not observed. Setae unbranched, septate, tapering to rounded at apical end, pale brown to dark brown, smooth-walled, 45-90 µm long, 5.9-6.2 μm wide at widest part, 2.6-5.8 µm wide at bottom, 1.5-1.6 µm wide at apex. Conidiophores pale brown, septate, branched. Conidiogenous cells pale, hyaline, smooth-walled, erect, clavate or cylindrical, 2-11 × 1-2 μm (x‒ = 6.3 ± 4.4 × 1.7 ± 0.4 μm, n = 20), L/W ratio= 3.7. Conidia hyaline, aseptate, smooth-walled, variable in size and shape, thick-walled, ellipsoidal to subglobose, the apex and base rounded, slightly constricted in the middle, 11-14 × 5-7 μm (x‒ = 13.1 ± 1.0 × 5.5 ± 0.6 μm, n = 40), L/W ratio= 2.4.

Culture characteristics.

Cultures on WA at 25 °C in darkness, reaching 15-18 mm diam. in 21 days, white to grey, asymmetrical surface, reverse dark grey to black.

Colonies on PDA at 25 °C reaching 45-55 mm diam. in 12 days in darkness, circular, more or less planar, surface dark brown, covered with abundant, pale grey, lanose to cottony aerial mycelium, margin smooth, entire and pale white. Reverse dark grey, margin pale white.

Cultures on CMA, 10-15 mm diam. in 21 days, covered with dark brown aerial mycelium, sparse, reverse light brown, margin irregular.

Material examined.

CHINA, Guizhou province, Tongren (27°35'37"N, 109°10'58"E, elevation 332.8 m), isolated from healthy stems of Nothapodytes pittosporoides , 27 May 2016, S.X. Zhou and L.J. Qiao (Holotype GACP GZU-TRJ1-37 dried culture), ex-type living culture, GMBC0209.

Notes.

Colletotrichum tongrenense belongs to the C. dracaenophilum species complex ( Damm et al. 2019). Morphologically, C. tongrenense resembles C. tropicicola and C. excelsum-altitudum in conidia characters, but it can be distinguished from C. tropicicola in having setae and longer conidia (15-19 µm vs 11-14 µm) ( Noireung et al. 2012). C. tongrenense is distinguished from C. excelsum-altitudum ( Tao et al. 2013) in having smaller conidiophores (2-11 × 1-2 μm vs 8.5-25 × 4-5 μm). Phylogenetically, the new isolate GZU_TRJ1-37 clusters together with C. tropicicola with good bootstrap support (94% MLBS, 1.00 PP) (Fig. 1) and the phylogenetic analysis supports it as a distinct species. There are 6, 4, 2 and 5 base pairs differences in ITS, TUB2, ACT and GAPDH gene regions, respectively, between the new isolate and the type strain of C. tropicicola , which confirms that they are separate species. Therefore, it is introduced as a novel species.