Calycina brevipes W. P. Wu

Calycina brevipes (Nag Raj & W. B. Kendr.) W. P. Wu, in Wu and Diao, Fungal Diversity 119: 277 (2023) Fig. 4 Holotype. HKAS 139498. Description. Saprobic on the dead leaf. Sexual morph: Apothecia scattered to partly gregarious, superficial, 1.1–2.4 mm in diameter, 0.9–1.8 mm high when dry, discoid to cupulate, shortly stipitate. Disc concave, surface slightly rough, cream when fresh and orange when dry. Margin flat to slightly involute, pale orange to orange. Receptacle discoid to cupulate, cream yellow to white when fresh and pale orange to orange when dry. Stipe 0.5–1.2 mm in diameter, 0.6–1.3 mm long when dry, cylindrical, solitary, pale orange to orange. Hymenium 61–88 µm (x – = 72 µm, n = 30), concave, surface smooth, orange to deeply orange when dry. Medullary excipulum 22–50 µm (x – = 33 µm, n = 25), thin, hyaline to light yellow, thin-walled, smooth cells of textura intricata to porrecta, 1.3–2.8 µm (x – = 2.0 µm, n = 50) in diameter. Ectal excipulum 15–34 µm (x – = 24 µm, n = 20), thin-walled, smooth, light yellowish cells of textura globulosa, 1.4–4.0 µm (x – = 2.6 µm, n = 60) in diameter. Paraphyses 48–73 × 1.0–2.5 µm (x – = 64 × 1.6 µm, n = 25), longer than asci, filiform, branched, straight to slightly curved, septate, hyaline, thin-walled, rough. Asci 42–65 × (3.2 –) 3.9–5.4 (– 5.7) µm (x – = 54 × 4.6 µm, n = 42), 8 - spored, partially biseriate, clavate, straight to slightly curved, inoperculate, hyaline, unitunicate, apically thin wall, slightly smooth, with an apical, rounded ends, J + in MLZ. Ascospores (50 / 14 / 2) (4.0 –) 5.0–7.1 (– 7.9) × 0.6–1.1 (– 1.3) µm, (x – = 6.8 × 0.9 µm), fascicled, fusoid-clavate with blunt ends, aseptate, thin-walled, hyaline, obtuse ends, without oil guttules, hyaline, slightly smooth. Asexual morph: See Wu and Diao (2023) Material examined. • China, Yunnan Province, Puer City, Jingdong County, Ailao Mountain, altitude 2451 m, on the decayed unknown leaf, 23 August 2022, Le Luo, ly 423 (HKAS 139498), ly 456 (HKAS 139499). Notes. According to the phylogenetic analyses, our collections (HKAS ly 423 and HKAS ly 456) clustered with the extant C. brevipes strains (8280 and 8302) with 100 % ML and 1.00 BP support (Fig. 1). Calycina brevipes was originally introduced as Chalara parvispora, and was later transferred to Calycina (Wu and Diao 2023), a saprobic fungus that was reported on the dead leaves of Podocarpus and other plants and distributed in Argentina, China and New Zealand (Nag Raj and Kendrick 1975; Gamundí et al. 1978). The anamorph of C. brevipes is characterized by the reduced conidiophores, consisting of one basal stalk cell and a terminal phialidic conidiogenous cell, clearly differentiated ellipsoidal venter and cylindrical collarette with a darker lower part, and aseptate, cylindrical conidia (Nag Raj and Kendrick 1975). However, in our collections, no asexual morphs were observed. Despite this, the identification of our collections as the sexual morph of C. brevipes is supported by molecular data. The ITS and LSU sequence data of our specimens (HKAS ly 423 and HKAS ly 456) exhibit 1.1 % and 0.8 % divergence, respectively, from the known C. brevipes strains 8280 and 8302. Given that these levels of genetic variation fall within intraspecific divergence thresholds and that all available strains of C. brevipes have only been known in their asexual state, we infer that our collections represent the previously unknown sexual morph of this species. Therefore, the current study presents the first report of the sexual morph of C. brevipes, marking its first record from Yunnan Province, China.