Tubeufia chiangmaiensis S. Boonmee & K.D. Hyde, sp. nov. I n d e x Fungorum number: IF 5507 0 5 .

Etymology: named after Chiang Mai, the location where it was collected.
Holotype: MFLU 11–1149

Saprobic on dead wood. Sexual state: Ascomata (200-)238–324 μm high× (180-) 227–269 μm diam. (x¼ 266  228μm ), superficial, solitary, scattered, globose subglobose to ovate, dark brown, with hyphae developing from ascomatal base onto substrate, slightly flat at the apex, brown to dark brown, ostiolate, collapsing when dry. Peridium 25–29μm wide, comprising 4–5 layers of brown to reddish-brown cells of textura angularis, and small, subhyaline to light brown cells of textura prismatica inwardly. Hamathecium comprising numerous, ca. 1–1.5μm wide, filiform, septate, branched, hyaline pseudoparaphyses. Asci (114.5-)120–137×11–14(−16) μm (x¼ 127  13μm , n=20),
8-spored, bitunicate, fissitunicate, elongate cylindrical to slightly clavate, apedicellate, thick-walled, rounded at apex, with an ocular chamber, tapering towards narrow base, sessile. Ascospores 46–53(−55.5)×(3.5-)4–4.5μm (x¼ 50  4μm , n=20), overlapping 2–3-seriate, cylindricfusiform, tapering toward ends, with pad-like mucilage at both ends, straight to slightly curved, 7-septate, not constricted at septum, hyaline, pale brown when mature, smooth-walled. Asexual state: Unknown.

Cultural characteristics: Ascospores germinating on MEA within 12 h and germ tubes produced from both ends. Colonies growing on MEA, reaching 5 mm in 7 days at 28 C, mycelium partly superficial, partly immersed, slightly effuse, radially striate, with fimbriate edge, dark-coloured; asexual spores not formed within 60 days.

Material examined: THAILAND, Chiang Mai, Mae Taeng, Mushroom Research Center, N19°17.123′ E 98°44.009′, elev. ca. 900 msl., on dead wood of an unidentified tree, 23 June 2011, Saranyaphat Boonmee MRC-06 (MFLU 11–1149, holotype); ex-type living cultures = MFLUCC 11–0514 = BCC 52386 = ICMP 20074.

Notes: Tubeufia chiangmaiensis has morphological characters typical of the genus, such as brown, globose-subglobose ascomata with basal mycelium, which darken when dry, fissitunicate, elongated, cylindrical-clavate asci, and cylindrical-fusiform, 7-transeptate, hyaline to pale brown ascospores, with pad-like mucilage at both ends. Tubeufia cylindrothecia has oblong translucent peridial ascomata, ascospores lack mucilaginous pad-like appendages and are smaller when compared to Tubeufia chiangmaiensis (Seaver 1909). Tubeufia chiangmaiensis differs from T. javanica in ascomatal and ascospore features (Penzig and Saccardo 1904; Rossman 1977; Sivanesan 1984, Fig. 3). Combined molecular analysis of LSU and ITS genes places T. chiangmaiensis and T. cylindrothecia (BCC 3559) within Tubeufia sensu stricto (Clade F) with strong support (100% BS and 1.00 PP).

Fig. 1 Tubeufia chiangmaiensis (MFLU 11–1149, holotype). a Ascomata on substrate. b L.S. of ascoma. c Peridium. d Hamathecium and pseudoparaphyses. e-g Asci. h-j Ascospores with mucilaginous pad-like appendage at both ends, marked by arrows. k Germinating ascospore. l, m Colonies on MEA from surface and reverse. Note dark brown colonies. Scale bars: a-b=100µm, c, h-k=30 mm, d=5µm, e-g=50µm, l-m=10mm