Rhopalostroma lekae Whalley, Thienh., M.A. Whalley & Sihan., Botanical Journal of Scotland 50(2): 188 (1998)

Index Fungorum number: IF 483748; Facesoffungi number: FoF 00017

Etymology – named in honour of the distinguished Thai mycologist, Leka Manoch.

Stromata per corticem erumpentia, solitaria vel laxe aggregata, pleurumque non ramosa, atrobrunnea ad purpureo-brunnea, 5-8 mm alta; stipes 3-5 mm altus et 1-2 mm latus, capitatus, capite leviter expanso, subgloboso 2.5-4 mm diam., caroe stipite nigra, carbonacea. Perithecia in parte superiore convexa in stromate immersa, 0.7-0.8 mm alta et 0.3-0.5 mm lata. Asci et paraphyses non visi. Ascosporae atrobrunneae, ellipsoideae, muffs laevigatis et uno distincto sulco longitudinali instructae, 7.5-10 x 2.8-5 μm.

Holotypus – in cortis emortis, Thailand, Nakon Ratchasima Province, Khao Yai National Park, Orchid Falls Trail, 30 Nov. 1996. T. Flegel, RFD Herbarium,
Bangkok.

Stromata erumpent through the bark, single or several clustered, occasionally branched, dark brown to purple-brown with sulphur yellow granules beneath the
surface, 5-8 mm tall; stipes 3-5 mm tall and 1-2 mm wide; head expanded, subglobose 2.5-4 mm diam.; flesh black and carbonaceous. Perithecia immersed in a layer beneath the surface of the ellipsoidal surface, 0.7-0.8 mm high x 0.3-0.5 mm wide. Ostioles umbilicate, appearing as minute dots. Asci and paraphyses not seen. Ascospores dark brown, ellipsoidal to reniform, with a straight, longitudinal germ slit on the convex side running the almost full length of the spore, smooth-walled, 7.5-10 × 3.8-5 μm.

Habitat – on bark. Known only from its type locality.

Fig. 1. Rhopalostroma kanyae (isotypus) stromal head. Bar marker 1 mm. Fig. 2. R. lekae (holotypus) stromata. Bar marker 2 mm. Fig. 3. R. kanyae (isotypus) SEM of ascospores showing germination slit. Bar marker 1 μm. Figs. 4 and 6. R. lekae (holotypus) ascopores. Bar marker 10 μm. Fig. 5. R. kanyae (isotypus) ascospore with germination slit. Bar marker 10 μm.