Scytalidium ganodermophthorum Kang, Sigler, Lee & Yun

8.Scytalidium ganodermophthorumKang, Sigler, Lee & Yun, Mycologia 102 (5): 1179 (2010) Xylogone ganodermophthora Kang, Sigler, Lee & Yun, Mycologia 102 (5): 1179. 2010. Synonym. Scytalidium parasiticum Yit K. Goh, Goh, Y. K. Goh & K. J. Goh, Mycobiology 43 (2): 112. 2015. Description and illustration. Kang et al. (2010). Notes. Scytalidium ganodermophthorum is phylogenetically closely related to S. synnematicum (Figs 1, 2). Morphologically, S. ganodermophthorum differs from S. synnematicum by its production of a sexual morph, arthroconidia, and not producing conidiomata or synnemata (Kang et al. 2010; Crous et al. 2023). Furthermore, based on a pairwise comparison of ITS, S. ganodermophthorum (ex-type UAMH 10320) differs from S. synnematicum (ex-type CCMB 207 / 13) by 9.6 % (50 / 520 bp, 16 gaps) in the ITS. Goh et al. (2015) established S. parasiticum based on morphological characteristics and phylogenetic analyses. However, in this study, S. parasiticum (ex-type AAX 0113) and S. ganodermophthorum (UAMH 10320, H 123, and TPML 97003) clustered in a single subclade with high supported value (100 / 1) (Figs 1, 2). In a comparison of ITS, S. parasiticum (AAX 0113) exhibited 99.8 % (515 / 516 bp, no gap) similarity to S. ganodermophthorum (ex-type UAMH 10320). Moreover, the morphological characteristics between S. parasiticum and S. ganodermophthorum are minor; therefore, we treat S. parasiticum as a synonym of S. ganodermophthorum. Scytalidium ganodermophthorum was first discovered in Korea as a pathogenic fungus causing yellow rot in cultivated Ganoderma lucidum (Kang et al. 2010), on which it behaves as an obligate or facultative parasite. While S. ganodermophthorum is a pathogen of G. lucidum, its synonym S. parasiticum has been shown to exhibit antagonistic effects against another Ganoderma species, the oil palm pathogen G. boninense, demonstrating its potential as a biocontrol agent (Goh et al. 2016).