Neoroussoella annulata H. L. Si, R. L. Chang, T. Bose & Y. C. Wang, 2025

Chang, Runlei, Yan, Zhaoqi, Jiang, Jibo, Wang, Yichen, Si, Hongli, Bose, Tanay & Miao, Congcong, 2025, Four novel endolichenic fungi from Usnea spp. (Lecanorales, Parmeliaceae) in Yunnan and Guizhou, China: Taxonomic description and preliminary assessment of bioactive potentials, MycoKeys 118, pp. 55-80 : 55-80

Neoroussoella annulata H. L. Si, R. L. Chang, T. Bose & Y. C. Wang sp. nov.

Fig. 6 a – h

Etymology.

The name refers to the zonate colony morphology on PDA.

Type.

China • Yunnan Province, Chuxiong Yi Autonomous Prefecture, Chuxiong City , Dayao County (26°32'71.54"N, 100°57'3.6"E), isolated from the medullary tissue of the lichen Usnea ceratina ( SDCX 26 ), 13 Nov. 2020, H. L. Si, CX 26 A 1 B = CGMCC 3.23625 (the ex-holotype culture), dried culture HMAS 352142 (holotype specimen), GenBank Accession Numbers: ITS OQ 645267 ; LSU OQ 645281 ; SSU OQ 645274 ; RPB 2 OQ 696278 ; TEF 1 OQ 696275 .

Description.

Hyphae smooth, pale coloured to brown, branched, septate, measuring 0.94-2.99 μm (x ̄ = 1.48 μm, n = 50) in diam (Fig. 6 c – h ). Often, two parallel hyphae form hyphal anastomosis (Fig. 6 d, g ). No spores or sexual morphs were observed.

Culture characteristics.

On PDA, after 7 days of incubation at 25 ° C, the colony has a light brown centre with curved elevations, surrounded by a greyish green concentric circle, and the margin is light grey. The surface is rough with short, fine hairs, and the edges are smooth and irregularly cracked (Fig. 6 a ). The reverse of the colony has a dark brown centre and edges that range from brown to yellow (Fig. 6 b ). The optimal growth temperature is 25 ° C (1.57 mm / day). No growth was detected at 5 ° C and 35 ° C.

Host.

Usnea ceratina .

Distribution.

Yunnan, China.

Note.

Neoroussoella annulata is closely related to N. magnoliae in both multigene and single-gene phylogenetic analyses. We didn’t observe any reproductive structures for N. annulata ; however, the sexual morph of N. magnoliae is known ( Yuan et al. 2020). A significant genetic divergence was observed between the species, with a total of 50 base pair differences in the sequences analysed: ITS (19 bps), SSU (21 bps), LSU (0 bps), and TEF (10 bps). Furthermore, the ecological preferences of these species are distinct; N. annulata was isolated from U. ceratina , whereas N. magnoliae is a saprobic species isolated from dead twigs of Magnolia species ( Yuan et al. 2020).

Figures

Figure 6. Morphology of Neoroussoella annulata sp. nov. (HMAS 352142) a top and b reverse view of a 15 - day-old culture growing on a PDA c – h hyphae; Veronaea brunneicolor sp. nov. (HMAS 352145) i top and j reverse view of a 15 - day-old culture growing on a PDA k, l hyphae; m – o conidiophore with conidia p, q conidia. Scale bars: 5 μm.