Scytalidium aurantiacum L. Beyer & Klingström

3. Scytalidium aurantiacum L. Beyer & Klingström View in CoL , Svensk bot. Tidskr. 59: 35 (1965)

Description and illustration.

Klingström and Beyer (1965).

Notes.

Scytalidium aurantiacum was established to accommodate strain FF 21 isolated from pine pulpwood and strain FF 29 obtained from birch ( Betula ) pulpwood ( Klingström and Beyer 1965). Scytalidium aurantiacum is phylogenetically closely related to S. album , S. assmuthi , S. rodionovae , S. circinatum , S. terrigenum , and S. tongrenense (Figs 1 View Figure 1 , 2 View Figure 2 ). The distinctions between S. aurantiacum and S. album / S. assmuthi are provided in the notes for S. album and S. assmuthi , respectively. Scytalidium aurantiacum is distinguished from S. rodionovae , S. terrigenum , and S. tongrenense by its unknown sexual morph and hyaline arthroconidia ( Klingström and Beyer 1965; Pavlov et al. 2018; Jeong et al. 2025). Scytalidium aurantiacum differs from S. circinatum by its bacilliformia arthroconidia, globose, or ellipsoidal chlamydospore-like cells ( Klingström and Beyer 1965; Sigler and Wang 1990). Additionally, based on a pairwise comparison of ITS and LSU, S. aurantiacum (ex-type CBS 374.65 ) differs from S. rodionovae (ex-type 3 C) by 9 % (49 / 531 bp, five gaps) in the ITS and 9.8 % (88 / 896 bp, 61 gaps) in the LSU; from S. circinatum (ex-type CBS 654.89 ) by 8.9 % (47 / 530 bp, five gaps) in the ITS and 3.2 % (19 / 590 bp, no gap) in the LSU; from S. terrigenum (ex-type KNUF- 23-236) by 2.5 % (13 / 528 bp, one gap) in the ITS and 8.4 % (822 / 897 bp, 62 gaps) in the LSU; from S. tongrenense (ex-type CGMCC 3.28994 ) by 6.3 % (33 / 522 bp, six gaps) in the ITS and 8.8 % (79 / 896 bp, 79 gaps) in the LSU.

This species not only causes blue stain in wood but also exhibits strong antagonistic effects against various wood-decaying fungi, particularly remaining effective at low temperatures (10 ° C) ( Klingström and Beyer 1965; Strunz et al. 1972; Cease et al. 1989). Furthermore, the antibiotic metabolite scytalidin produced by S. aurantiacum has demonstrated antifungal activity, making it a candidate for antifungal agent development ( Ayer et al. 1993). Dirginčiutė-Volodkienė and Pečiulytė (2011) demonstrated that S. aurantiacum exhibits significant tolerance to copper pollution, indicating its potential as a bioindicator for copper contamination and a candidate species for bioremediation applications.