Colletotrichum reineckiae Y.X. Zhang, J.W. Chen, Z.L. Mai, & Manawas., sp. nov.

MycoBank number: MB; Index Fungorum number: IF; Facesoffungi number: FoF 10612;

Etymology – Epithet refers to the host genus name Reineckia.

Holotype – ZHKUCC 21-0079

Micromorphology: Associated with leaf spot of Reineckia carnea (Andr.) Kunth. Sexual morph: not produced. Asexual morph: Conidia 14–17 × 4–6 μm (ave. 15 × 5 μm, n=50), formed with mycelium, one-cell, smooth-walled, most slightly rounded at the end, slightly curved at one end, some rounded at both ends. Appressoria in slide cultures, formed from branched mycelia, brown, some oval to nearly rhombus or quincunx and often becoming complex with age, 10–16 × 4–7 (–8) μm (x̅ 12 × 6 μm, n=50).

Culture characteristics: Colonies on PDA attaining 68 diam in 7 days at 25 ℃, growth rate per day 4.6mm±0.5/d (n=4), at first white, becoming light brown, in reverse pale yellowish. Aerial mycelium greyish white, dense, cottony, without setae and Sclerotium produced.

Material examined: China, Guangdong province, Shenzhen Botanical Garden, 30th November 2020, J.W. Chen, Z.H. Zhang and C. Chen (dried cultures ZHKU 21-0072 holotype; ZHKU 21-0073 paratype), and living culture, ZHKUCC 21-0079 ex–holotype; ZHKUCC 21-0080 ex–paratype.

Notes: Colletotrichum reineckiae is introduced as a new species based on morphology and phylogenetic evidence. This new species is grouped with C. pandanicola with low support (44% ML and 32% MP). The colony of C. pandanicola is white in the beginning and later become dark grey later, its conidia is 9–18 × 4–8 μm (x̅ 13 × 5 μm, n = 20), cylindrical with rounded ends tapering slightly towards the base (Tibpromma et al., 2018). C. reineckiae is white and become light brown later, pale yellowish in reverse. Its conidia 14–18 ×4–6 μm (ave. 15 × 5 μm, n=50), most slightly rounded at the end, slightly curved at one end, some rounded at both ends.

Fig. Colletotrichum reineckiae (ZHKUCC 21-000079: Holotype) a, b. Upper and reverse view on PDA after seven days. c-i. Appressoria. j, k.Conidia. Scale bars: c–k = 10 µm.