Hermatomycetaceae » Hermatomycetaceae » Hermatomyces

Hermatomyces krabiensis

Hermatomyces krabiensis Tibpromma, Bhat & K.D. Hyde, in Tibpromma, Bhat, Doilom, Lumyong, Nontachaiyapoom, Yang & Hyde, Phytotaxa 275(2): 132 (2016)

  Index Fungorum number: IF552307            Facesoffungi number: FoF02479

 

Saprobic on dead leaves of Pandanus odorifer. Sexual morph: Undetermined. Asexual morph: Colonies on natural substrate dry, blackish brown, velvety, circular, dull, consisting of a sterile mycelial outer zone and a round, glistening, abundantly sporulating centre, with conidia readily liberated when disturbed. Mycelium 1.0–3.7 μm wide, superficial, composed of a network of branched, septate, brown, thick-walled hyphae. Conidiophores 3.1–8.4 μm long, 2.1–3.3 μm wide, micronematous, straight or flexuous, hyaline, septate, smooth, unbranched, arising from prostrate hyphae at the centre of circular colony. Conidiogenous cells holoblastic, monoblastic, integrated, terminal, cylindrical, hyaline to subhyaline. Conidia dimorphic, thick-walled, smooth: lenticular conidia 24.3–32.5 μm high, 12.1–21.3 μm diam wide ( x = 28.5 × 17.2 μm, n = 30), multiseptate, with central cells dark brown to black, with peripheral cells subhyaline to pale brown, slightly constricted at the septa, smooth, in side view composed of one column of 4–6 cells, hyaline to light brown at the lower and upper cells, often carrying remnant of conidiogenous cell at base; cylindrical conidia: 20.4–26.4 μm high, × 8.6–19.7 μm wide in broadest part of lower cells, ( x = 23.2 × 14.2 μm, n = 20), with 1–2 columns of 2–3 cells arising from a common basal cell, each column, with rectangular to globose cells, constricted at septa, pale to subhyaline, granulate, smooth, terminating with a dark brown, turbinate upper cell.

Culture characteristics: Colonies on MEA at room temperature (22–25°C) reaching 4 cm in 1 week, circular with entire, white-grey mycelium with white in the margin, smooth at surface and raised, not sporulating in culture even after 4 months.

 

Material examined: THAILAND, Krabi Province, on dead leaves of Pandanus odorifer (Pandanaceae), 14 December 2015, S. Tibpromma & K.D. Hyde KB007 (MFLU16-1885, holotype; HKAS94528, isotype); ex-type living culture, MFLUCC16-0249.

 

Notes: Hermatomyces krabiensis shares a similar morphology with H. amphisporus. Both taxa produce lenticular and cylindrical conidia. Hermatomyces krabiensis however, is distinct, with cylindrical conidia bearing 1–2 columns of 2–3 cells arising from a common basal cell. In H. amphisporus, the conidia are composed of 6–11 cells arranged in 4 rows (Castañeda & Heredia 2000).