Chlorencoelia torta (Schwein.) J.R. Dixon, Mycotaxon 1(3), 230 (1975)

Index Fungorum number: IF 311053; Facesoffungi number: FoF 13909; Fig. 1

Saprobic on decayed wood barks. Sexual morph: Apothecia 2–4 × 2–3.1 mm (x̄= 3.1 × 2.5 mm, n = 5) in dry condition, arising singly or in small cluster, stipitate. Receptacle cupulate, olivaceous dark brown to black. Stipe 1.1–1.9 × 0.6–0.9 mm ( = 1.5 × 0.8 mm, n = 5) in dry condition, concolorous with receptacle, rugose. Disc dark brown, shallow cupulate to infundibuliform convex with enrolling edges upon drying. Ectal excipulum 54–106 µm (x̄ = 79.5 µm, n = 15), composed of thin to thick-walled, hyaline to dark brown cells of textura angularis. Medullary excipulum 119–169 µm (x̄ = 143.4 µm, n = 15) in lower flanks, composed of thin-walled, hyaline to yellowish cells of textura intricata. Hymenium 129–181 µm (x̄ = 170.6 µm, n = 15). Paraphyses 2.4–3.7 µm in diam. (x̄ = 2.8 µm, n = 30) at the apex, filiform, occasionally slightly swollen at the apex, septate, sometimes guttulate. Asci 95–115 × 4.4–6.9 µm (x̄ = 105.3 × 6 µm, n = 15), unitunicate, 8-spored, cylindrical, rounded to subconical apex, amyloid, long substipitate base, arising from croziers. Ascospores 6.2–8.4 × 2.4–3.4 µm (x̄ = 7.3 × 3 µm, n = 20), uniseriate, ellipsoid, hyaline, biguttulate, rounded at both ends. Asexual morph: Undetermined.

Material examined – Thailand, Kew Mae Pan trail, Doi Inthanon, Chomthong District, Chiang Mai Province, bark of an unknown host, 20 October 2021, Pi Usa, KMP3-7B (MFLU 23-0016)

GenBank accession numbers – ITS: OP64490, LSU: OP622874.

Known distribution (based on molecular data) – China (Pärtel et al. 2017, Zhuang et al. 2000), Korea (Han et al. 2014, Kim et al. 2015), New Zealand (unpublished), the USA (Raja et al. 2011, Pärtel et al. 2017), Thailand (this study).

Known hosts (based on molecular data) – Fuscospora fusca (unpublished), Leptospermum scoparium (unpublished), rotten deciduous wood (Pärtel et al. 2017).

Notes – Our species fit the description of Chlorencoelia torta by having black to olivaceous dark apothecia, ectal excipulum of textura angularis cells, medullary excipulum of textura intricata cells, and ellipsoidal ascospores (Fig. 1). Chlorencoelia torta has been previously recorded in Japan, New Zealand, North America, Puerto Rico, the Soviet Union, and Tasmania on decayed wood of Acer, Betula, Fagus, Quercus, Tabebuia, coniferous and unidentified wood (Dixon 1975, Han et al. 2014, Pärtel et al. 2016). Morphologically, our specimen (MFLU 23-0016) is similar to the holotype of C. torta (CUP 51760) designated by Dixon (1975), even though the paraphyses septation in our specimen is irregular. However, the phylogenetic relationship between our species and the holotype cannot be ascertained, as sequence data are unavailable for the type specimen. Phylogenetic comparison can only be assessed for the species to whom sequence data is provided by Pärtel et al. (2017) and Han et al. (2014), as no other studies have been conducted on C. torta. Based on the phylogenetic analysis of combined ITS and LSU sequences, our isolate (MFLU 23-0016) clustered with the isolates of C. torta from China, New Zealand, and Korea with 91% maximum likelihood bootstrap support and 1.00 Bayesian posterior probability (Fig. 2).

Fig. 1 – Chlorencoelia torta (MFLU 23-0016, a new geographical record). a Bark pieces of a decayed log. b–c Apothecia on the substrate. d Cross section of an apothecium. e Close up of the hymenium at the margin. f Close up of the ectal excipular cells. g Close up of the medullary excipular cells. h–i Slightly apically swollen paraphyses (mounted in Congo red). j–k Asci (mounted in Congo red). l J+ ascal tip (mounted in Melzer agent). m–n Ascospores (m mounted in Congo red). Scale bars: b–c = 1 mm, d = 450 µm, e = 155 µm, f–g = 17 µm, h–k = 15 µm, m–n = 8 µm.

Fig. 2 – Phylogram generated from RaxML analysis based on the combined ITS and LSU sequence data of Cenangiaceae. Forty-one strains are included in the combined analyses, which comprised of 1303 characters (468 characters for ITS and 835 for LSU). Tree topology of the maximum likelihood analysis is similar to the Bayesian analysis. The best RaxML tree with a final likelihood value of -6924.87 is presented. The matrix had 367 distinct alignment patterns, with 25.9% of undetermined characters or gaps. Evolutionary model applied for both genes is TIM2+I+G. Maximum likelihood bootstrap values equal to or greater than 70% and Bayesian posterior probabilities equal to or greater than 0.95 (MLBS/BYPP) are given at the nodes, respectively. The tree is rooted to Sclerotinia sclerotiorum (CBS 577.77) and Rutstroemia firma (KL291). The type strains are indicated in bold and newly generated strains are in red.