Hysteriales » Hysteriaceae » Hysterium

Hysterium angustatum

Hysterium angustatum Alb. & Schwein., Consp. fung. (Leipzig): 55 (1805)

Facesoffungi number: FoF 04579


Sexual morph: Ascomata 207.5–294.5 μm high × 242.5–346 μm diameter (x̄ = 238.5 × 278 μm), hysterothecial, erumpent to entirely superficial, solitary, or gregarious, oval or ellipsoid to greatly elongate, straight to curved, scattered, dark, carbonaceous, brittle, with a sunken longitudinal slit-like opening. Peridium 42–57 μm wide, composing thick layers of dark brown cells of carbonaceous texture, inner layers composed of several layers of light brown to brown cells of textura angularis. Hamathecium comprising 1–2 μm thin, cylindrical, hyaline, branched, septate, anastomosing pseudoparaphyses. Asci 67.5–92 × 13–20.5 μm (x̄ = 80 × 17 μm, n = 10), 8-spored, bitunicate, fissitunicate, saccate, broadly clavate to cylindrical, slightly curved, short pedicellate, with knob-like pedicel, apically rounded, with a well-developed ocular chamber. Ascospores 20–31 × 7–10 μm (x̄ = 23.5 × 8.5 μm, n = 20), overlapping 2-seriate, brown to greenish brown, fusiform, oblong or ellipsoidal to cylindrical, 3-septate, constricted at the median septum, smooth-walled. Asexual morph: Undetermined.


Culture characteristics: Ascospores germinating on WA within 12 h and germ tubes produced from both cells. Colonies on MEA 0.2 mm after 7 days at 28 °C. Mycelium superficial, low convex, slightly effuse hairy, edge entire, grayish-brown to brown. Aerial mycelium, radiating outwards, superficial, septate, hyaline to brown, smooth-walled.


Host and habitat: on bark of living Pinus rigida (Boehm et al. 2009), on dead aerial branch of Rubus sp. (Jayasiri et al. 2018), on dead wood of unidentified host (Hyde et al. 2020).


Known distribution: Kenya, New Zealand, South Africa, United States (Boehm et al. 2009), Italy (Jayasiri et al. 2018) and Thailand, Chiang Mai Province, (Hyde et al. 2020).


Material examined: Thailand, Chiang Mai Province, Chom Thong District, on dead wood, 16 November 2010, R. Phookamsak, ITN06 (MFLU 11–0004, new geographical record), living culture (MFLUCC 11–0004 = BCC 52154).


GenBank Accession No: ITS: MN608547, LSU: MN577416, SSU: MN577427.


Notes: The strain MLFUCC 11–0004 is phylogenetically related to other Hysterium angustatum isolates with high statistical support (94% ML/1.00 BYPP) (Hyde et al. 2020). In addition, our strain shares similar morphologies in shape, size and pigment of ascomata, asci and ascospores with Hysterium angustatum (CBS 236.34, CBS 123334, CMW 20409, GKM 243a, GKM 5211, MFLUCC 16–0623, SMH 5216). Therefore, based on morphology and phylogenetic affinity, our strain MFLUCC 11–0004 is identified as Hysterium angustatum and it is reported here as a new geographical record from Thailand.