Hysteriales » Hysteriaceae » Rhytidhysteron

Rhytidhysteron thailandicum

Rhytidhysteron thailandicum Thambug. & K.D. Hyde, Cryptog. Mycol. 37(1): 110 (2016) Facesoffungi number: FoF 01841


Sexual morph: Hysterothecia 1000–1800 μm long × 300–500 high × 500–1200 μm diameter ( = 1400 × 420 × 850 μm, n = 10), arising singly or in small groups, sessile, slightly erumpent from the substrate. Receptacle cupulate, black, flat or slightly concave, yellowish brown when fresh, with slightly dentate margin. Excipulum 40–70 μm wide, ectal excipulum narrow layered, deep, thick-walled, with black cells of textura globulosa to textura angularis; medullary excipulum composed of narrow, long, thin-walled, hyaline to brown cells of textura angularis. Hamathecium comprising 2–5 μm wide, numerous, propoloid, apically swollen, branched and pigmented, branched paraphyses, exceeding asci in length, apices form a layer on the hymenium to develop the epithecium. Asci 120–150 × 12–16 μm ( = 130.1 × 15.3 μm, n = 30), 8-spored, long cylindrical, short pedicellate, rounded at the apex. Ascospores 20–32 × 7.5–10.5 μm ( = 23.3 × 8.6 μm, n = 40), uniseriate, dark brown, ellipsoid with conical ends, regularly 3-septate, smooth-walled, guttulate. Asexual morph: coelomycetous. See Thambugala et al. (2016, Pages 15, 16) for more details.


Culture characteristics: N/A.


Host and habitat: on dead twigs of Afzelia xylocarpa (Hyde et al. 2020), on dead twigs (Thambugala et al. 2016), on dead twigs of an undetermined tree (Hyde et al. 2020), dead wood (Yacharoen et al. 2015).


Known distribution: Thailand, Chiang Rai Province (Thambugala et al. 2016, Hyde et al. 2020), Thailand, Phitsanulok Province (Yacharoen et al. 2015), China, Yunnan Province, Qujing City (Hyde et al. 2020).


Material examined: China, Yunnan Province, Qujing City, 24.68703° N, 104.24653° E, 1618m, on dead twigs of an undetermined tree, 6 May, 2019, Dhanushka N. Wanasinghe (MFLU 19-2373).


GenBank Accession No: ITS: MN989428, LSU: MN989429, SSU: MN989430, tef1: MN989431.


Notes: Rhytidhysteron thailandicum was introduced by Thambugala et al. (2016), which was collected from Thailand (on a dead twig). During our investigation on diversity of microfungi in China, a specimen was recovered from a dead twig in Qujing, Yunnan Province. Morphological characters such as ascomata, asci and ascospores fit well within the sexual morph of Rhytidhysteron thailandicum. We did not obtain an isolateand therefore we isolated DNA directly from the fruiting bodies. Comparison of ITS and tef1sequence data reveals there is no significant difference (< 3 bp differences) between our new collection and the type strain (MFLUCC 14-0503). Therefore, we introduce our new collection as a new geographical record herein.