Conioscypha yunnanensis L. Li, Bhat & Phookamsak, 2024

Li, Lu, Du, Hong-Zhi, Thiyagaraja, Vinodhini, Bhat, Darbhe Jayarama, Phookamsak, Rungtiwa & Cheewangkoon, Ratchadawan, 2024, Two novel freshwater hyphomycetes, in Acrogenospora (Minutisphaerales, Dothideomycetes) and Conioscypha (Conioscyphales, Sordariomycetes) from Southwestern China, MycoKeys 101, pp. 249-273 : 249

Conioscypha yunnanensis L. Li, Bhat & Phookamsak sp. nov.

Fig. 4

Etymology.

The specific epithet " yunnanensis " refers to the name of the region, Yunnan Province (China), from where the holotype was collected.

Holotype.

KUN-HKAS 129616.

Description.

Saprobic on submerged wood and unidentified twigs from freshwater habitat. Asexual morph: Hyphomycetous. Colonies on natural substrates effuse, black, glistening. Conidiophores reduced to conidiogenous cells. Conidiogenous cells phialidic, integrated, terminal, globose to subglobose, cup-shaped, percurrently proliferating in the same level, becoming multi-layered, multi-collaretted with outwardly curved edge, hyaline, smooth-walled. Conidia 18-26 × 17-22 µm (x - = 22 × 20 µm, n = 20), acrogenous, brown to dark brown, globose to subglobose, smooth-walled, aseptate, rounded at apex, subtruncate at base. Sexual morph: Undetermined.

Culture characteristics.

Conidia germinating on PDA within 48 h and germ tubes produced from the conidial base. Colonies reaching 4.3 mm diam at room temperature in natural light for three months. Colonies on PDA medium dense to dense, circular, white and gray in the center, with packed mycelium, becoming black mycelial patch in the middle, white to cream at the margin, slightly radiating with irregular edge, radially furrowed aspect; in reverse, dark brown to black at the center, radiated with pale yellowish and dark greenish furrowed ring, white to cream at the margin with furrows aspects; no pigmentation on PDA.

Material examined.

China, Yunnan Province, Xishuangbanna (21°10'- 22°40'N, 99°55'- 101°50'E), on decaying submerged wood in a freshwater stream, 9 September 2022, L. Li, LILU-117-1 (KUN-HKAS 129616, holotype), ex-type living culture = KUNCC 23-13319; Dujuanhu Lake (22°29'- 25°30'N, 100°16'- 103°16'E), on unidentified twigs, 26 August 2022, LILU-109-1 (KUN-HKAS 129617, paratype), living culture KUNCC = 23-13172 .

Notes.

Conioscypha yunnanensis has close phylogenetic relationships with C. peruviana and C. minutispora . The nucleotide base pair comparison between C. yunnanensis (KUNCC 23-13319) and C. peruviana (CBS 137657) revealed 95/828 bp (11.2%) of LSU differences. The nucleotide base pair comparison between C. yunnanensis (KUNCC 23-13319) and C. minutispora (FMR 11245) revealed 57/623 bp (9.2%) of LSU, 118/554 bp (22%) of ITS and 10/937 (1.1%) of SSU differences. The new taxon shares similar morphology with C. peruviana in having cup-like phialidic conidiogenous cells, and brown conidia but differing by varied shapes (globose to subglobose vs. ellipsoidal to allantoid or fabiform), the size (18-26 × 17-22 µm vs. 13.5-18 × 5-8.5 µm) and absence of lipid droplets ( Zelski et al. 2015). Conioscypha yunnanensis also resembles C. minutispora in having subglobose conidia but differs in the size measurement (18-26 × 17-22 µm vs. 6-9 × 5-6 µm) ( Crous et al. 2014). Furthermore, C. yunnanensis shares similar morphology to the type species C. lignicola in having micronematous conidiophores and globose to subglobose conidia that are brown. However, C. yunnanensis differs by the absence of dark brown ring surrounded in the conidia and presence of guttules periphery of conidia ( Shearer 1973). The morphological comparison with other Conioscypha species is also provided in Table 3 .

Figures

Figure 4. Conioscypha yunnanensis (KUN-HKAS 129616, holotype) a host specimen b colonies on submerged wood c conidiogenous cells bearing conidia (note: arrow points = cupulate conidionenous cells) d, e conidiogenous cell attached with conidia f-m conidia n germinated conidium o, p colony on PDA (o = up-front, p = down-reverse). Scale bars: 20 μm (c-n).