Kirschsteiniothelia tectonae Doilom, D.J. Bhat & K.D. Hyde, sp. nov.
Index Fungorum number: IF 551992, Facesoffungi number: FoF 01883, Fig. 2
Etymology: Name refers to the host genus Tectona on which the fungus was collected.
Holotype: MFLU 15–1883.

Saprobic on dead branches and twigs of Tectona grandis (L. f.). Sexual morph Undetermined. Asexual morph Colonies on natural substrate, superficial, hairy, dark brown, scattered, single or in groups. Conidiophores up to 200 μm long, 4 – 8 μm wide at the swollen base, superficial on host surface, macronematous, mononematous, simple, erect to slightly curved, unbranched or branched, septate, slightly constricted at septa, pale brown to dark brown, cylindrical. Conidiogenous cells 7.5 – 9.5 × 3.5 – 5 μm, monoblastic, integrated, terminal, cylindrical, determinate. Conidia (85–)135 – 150(–212) × (15–)16 – 17( –19) μm ( x̄ = 137 × 16 μm, n = 30), 9 – 25 or more transverse septa, cylindric- obclavate, elongate, straight or slightly curved, rounded at the apex and slightly paler, with sheath at apex, obconically truncate at the base, dark reddish brown, thick–walled, smooth; secession schizolytic.

Culture characteristics: Conidia germinating on PDA within 24 h. Colonies on MEA reaching 14 – 16mm diam. after 7 days in the dark at 25 °C (x̄ = 14.9 mm, n = 5), entire edge, circular, flat or effuse, raised at the edge, superficial at the center, dense, fluffy, grey (5E1) from above, brownish (5 F2) from below. Mycelium 1.5 – 4.7μm wide, aerial, reddish brown to dark brown, septate, branched hyphae, slightly constricted at septa. Conidiophores up to 45 μm long, 3.5 – 8 μm wide, semi-macronematous, mononematous, erect to slightly curved, indeterminate, branched, reddish brown to dark brown. Conidiogenous cells holoblastic, doliiform, integrated, terminal. Conidia (33–) 70 – 110 (–200) μm long × (7–) 11 – 13 (–18) μm thick at the broadest part (x̄ = 83 × 12 μm, n = 30), produced on aerial mycelium, initially subglobose and acellular, becoming cylindric-obclavate, 1 – 29 or more transverse septa, flexuous, slightly curved, rounded at the apex and slightly paler, obconically truncate at the base, dark reddish brown, thick-walled.

Material examined: THAILAND, Phrae Province, Denchai District, Ban Maejour Subdistrict, on dead branches of Tectona grandis (Lamiaceae), 29 October 2011, M. Doilom (MFLU 15–1883, holotype), ex-type living culture MFLUCC 12–0050, MKT 016, MUCL55897; Chiang Rai Province, Mae Chan District, on dead twigs of T. grandis, 3 March 2013, M. Doilom, MFLU 15–1884, living culture MFLUCC 13–0470, MKT 111.

Notes: Kirschsteiniothelia tectonae was found only in its asexual morph, while K. thujina is known only as the sexual morph. Thus, a morphological comparison could not bemade, and K. tectonae is only compared to K. atra, K. emarceis and K. lignicola. These three species have been reported with asexual morphs both on natural substrates and cultures. It differs from these species in size and shape of conidiophores and conidia both on natural substrates and cultures. The conidia of K. tectonae are longer than those of the other three species (Table. 1). Based on its morphology (Fig. 2) and the fact it is phylogenetically separate from other species in Kirschsteiniothelia (Fig. 45), we introduce it a new species. The combined LSU, SSU and ITS sequence analysis shows that K. tectonae isolate MFLUCC 12–0050 and MFLUCC 13–0470 grouped close to, but is distinguishable from K. thujina with strong bootstrap support 100 % MPBS and 1.00 PP (Fig. 1).

Fig. 1 Phylogram generated from combined LSU, SSU and ITS sequence data. The tree is rooted to Dothidea insculpa CBS 189.58. Maximum parsimony bootstrap values ≥50 %, Bayesian posterior probabilities ≥ 0.95, (MPBS/PP) are given at the nodes. The ex-type strains are in bold and the new isolates are in blue.

Fig. 2 Kirschsteiniothelia tectonae (holotype) a Conidia host surface (arrows) b – d Conidia e Colony on MEA for 7 days (above and below views) f Colony on PDA for 2 months (above and below views) g Mycelia h Immature conidia attached to conidiophore i Conidia j – m, o Conidia attached to conidiophores with mycelia n, p Conidia attached to conidiophores a – d Morphology on host g – p Morphology on MEA culture. Scale bars: a = 200 μm, b – d, g, j, n–p = 20 μm, h, i, l, m = 10 μm, k = 50 μm.