Chaetosphaeria panamensis – Facesoffungi number: FOF 02657

Chaetosphaeria panamensis Huhndorf & F.A. Fernández, Index Fungorum number: IF344227

Saprobic on dead wood. Sexual morph: Ascomata 180–230 μm diameter, 195–285 μm high, scattered, sparse, superficial, not collapsing when dry, reddish-brown to dark brown, setose, rough-walled, papillate. Setae scattered over entire ascomata, dark brown, stiff, pointed, 60–85 μm long. Peridium 28–45 μm thick, with cells of textura globosa in surface view, 2-layerd in longitudinal section, inner layer 6–10 cells thick, comprising small, brown to dark brown, elongate to polygonal cells, with setae arising from inner layer, outer layer 4–6 cells thick, composed of large isodiametric to polygonal, brown to dark brown cells. Paraphyses 4–4.8 μm wide at the base, tapering towards the apex, numerous, septate. Asci 120–140×10–11.3 (x̅ = 130.8×10.6, n = 10) μm, 8-spored, unitunicate, arising from the basal hymenium, cylindrical, rounded at the apex, with a J-, apical ring. Ascospores 60–73×3–4.1 (x̅ = 68.2×3.5, n = 20) μm, filiform, loosely fasciculate, straight or slightly curved, 7-septate, without constrictions at the septum, rounded at both ends, apical end broader than the basal end, hyaline, smooth walled. Asexual morph from the culture: colonies on MEA cream coloured to light brown. Conidiophores macronematous, mononematous, flexuous, septate, branched, smooth, pale to moderately brown. Conidiogenous cells 4.3–5.3×1.5–2.1 μm, phialidic, flask-shaped to clavate, arising on septate, brown conidiophores, hyaline to light brown, guttulate, terminating with a flared conspicuous, cup-shaped collarette. Conidia 14.6–17×10–14.8 (x̅ = 15.6×12.3, n = 20) μm, enteroblastic, hyaline, 1-celled, globose to subglobose or ellipsoid, guttulate. Aleuriospore-like cells absent.

Culture characters: Twenty-one day old colonies on MEA, 55–58 mm diameter, mostly immersed, with floccose superficial hyphae, margins effuse, light brown from above, reverse dark brown, producing asexual morph after 60 days of incubation in the dark at 28 °C.

Material examined: THAILAND, Chiang Mai Province, garden of Mushroom Research Center, on decorticated twig of Pinus (Pinaceae Spreng. ex F.Rudolphi), 12 July 2015, R.H. Perera, RHP 116 (MFLU 16-1014), living culture, MFLUCC 15-1011.

Notes: Our newly collected strain (MFLUCC 15-1011) clustered with the ex-type strain of Chaetosphaeria panamensis (SMH 3596), collected from wood fragment in Panama. The ascomata, size of asci, ascospores and asexual morph of our strain is typical of C. panamensis in the shape and size (Fernández & Huhndorf 2005) and the ITS molecular data is identical to SMH3596, which is the only gene available for the ex-type. Here, we provide additional LSU, ITS and TUB sequence data for the species. This is the first record of C. panamensis for Thailand.

Fig. 1 Chaetosphaeria panamensis (MFLU 16-1014) a, b. Appearance of ascomata on host substrate. c. Section of ascoma. d. Paraphyses. h, i. Asci. j. Ascospores. k. Germinating ascospore. m, n. Colony on MEA (above and below). Bars – c = 100 μm, d, e = 50 μm, f–l = 20 μm.