Dicephalospora irregularis Lestari, Pasouvang & K.D Hyde, sp. nov
Mycobank number: MB 555157; Index Fungorum number: IF 555157; Facesoffungi number: FoF 11034;
Etymology:—“irregularis” refers to irregular shape of apothecia.
Holotype:— MFLU XXXXXX
Saprobic on dead stems and twigs of unknown tree. Sexual morph: Apothecia 0.5–1.3 × 0.3–1.2 mm, round to irregular in shape, arising singly or in small groups, sessile, erumpent. Receptacle discoid, orange to yellow-brown. Margins smooth, brown to dark orange. Disc slightly convex, orange. Ectal excipulum 30–45 µm (= 40 µm, n = 15) in lower flanks, composed of thick-walled, yellowish cells of textura globulosa to textura angularis. Medullary excipulum 42–63 µm ( = 48.8 µm, n = 15) in lower flanks, composed of thin-walled, yellowish to hyaline, gelatinized cells of textura porrecta to textura intricata. Hymenium hyaline to yellowish. Paraphyses 2.5–4.0 µm wide (= 3 µm, n = 15) at the terminal cell, filiform, numerous, length exceeding the asci, unbranched to branched at the top with gelatinous matters, apically rounded, aseptate, guttulates. Asci 125–150 × 15–20 µm (= 135 × 17 µm, n = 15) 8-spored, unitunicate, cylindrical clavate, nonamyloid (J-, in Melzer agent with or without KOH treatment), rounded apex, arising from simple septa without basal protuberance. Ascospores 25–35 × 5.5–7.5 µm (= 33 × 7.5 µm, n = 15), uniseriate to biseriate, fusoid-clavate to ellipsoid, pointed ends with gelatinous caps, hyaline, septate when mounted in Melzer agent, guttulates. Asexual morph: Undetermined.
Material examined:— Thailand, Chiang Mai Province, Mae Taeng District, Pa Pae. On dead stems of dicotyledone. 09 September 2020, Pahua Pasouvang, CM 31 (MFLU HT xx-xxx, holotype).
GenBank accessions:— ITS-xxxx, LSU xxxx
Notes:— Our collection CM 31 grouped sister to Dicephalospora rufocornea MFLU 18-1825 and HMAS 279697 (Fig. 1). The ITS sequence of our specimen shows xx simlarity to the D. rufocornea (TNS:F-40024) LSU data of our collection shows 99% similarity with gaps to that of D. rufocornea (TNS: F-40024).
Figure 6. Dicephalospora irregularis (MFLU 21-0018, holotype). (A) dead twig substrate; (B–D) Top and side view of apothecia; (E) A cross section of an apothecium; (F) Cells of ectal excipulum; (G) Cells of medullary excipulum; (H–I) A branched paraphyses; (J–M) Asci (Mounted in Meltzer agent; (N–O) Ascospores (Mounted in KOH 5%). Scale bars (B–D) = 500 µm; (E) = 200 µm ; (F–G) = 13 µm; (H–L) = 25 µm; (N) = 20 µm.