Brahmaculus osornoensis M.E.Sm. & P.R.Johnst., 2021

Johnston, Peter R., Park, Duckchul, Smith, Matthew E., Mujic, Alija B. & May, Tom W., 2021, Brahmaculus gen. nov. (Leotiomycetes, Chlorociboriaceae), MycoKeys 80, pp. 19-43 : 19

Brahmaculus osornoensis M.E.Sm. & P.R.Johnst. sp. nov. Figure 5

Typification.

Chile • Parque Nacional Vicente Perez Rosales , Volcan Osorno, on the road to the ski area just above Mirador el Bosque, Nothofagus dombeyi forest; -41.1382, 72.5370; Matthew Smith and Alija Mujic (MES2942) leg.; 17 April 2017; SGO - holotype; FLAS-F-65492 - isotype; PDD 116649 - isotype.

Etymology.

Refers to the type locality, Volcan Osorno.

Diagnosis.

Phylogenetically distinct from other known Brahmaculus spp., apothecia 3-6 × 1-2.5 mm, paraphyses taper slightly to rounded apex, ascospores 6.5-10(-11) × 1.5-2 µm (average 8.3 × 2 µm).

Description.

Apothecia 3-6 mm high, stipe 0.5-1 mm wide, cap 1-2.5 mm wide, the more or less globose cap comprising several closely packed apothecial cups, these arising from short, branches at the top of the stipe, hymenium pale yellow, hymenial areas broken into smaller segments by groups of bright yellow, hair-like elements amongst the fertile parts of the hymenium. Receptacle densely covered with stiff, bright yellow hairs, stipe with shorter hairs. Hairs 50-85 × 2.5-4 µm, straight, with a broad basal cell then cylindric, apically tapering suddenly to the narrow-rounded apex, thin-walled, sparsely septate, densely encrusted with coarse, bright yellow crystals that dissolve in KOH + Melzers. In squash mount, excipular cells broad-cylindric, about 15-30 × 8-12 µm, wall slightly thickened, hyaline. Paraphyses 2-2.5 µm, tapering slightly to rounded apex, about same length as asci. Asci 40-50 × 4-4.5 µm, cylindric, apex rounded, wall thickened, amyloid pore extends through the wall, flaring slightly towards the outside. Ascospores 6.5-10(-11) × 1.5-2.5 µm (average 8.3 × 2.0 µm, n = 50), oblong elliptic, ends rounded, one side flat in side view, sometimes slightly curved, 0-septate, hyaline.

Notes.

The two Chilean species differ macroscopically, Brahmaculus osornoensis having noticeably broader stipes than B. magellanicus and slightly longer ascospores. B. osornoensis is known only from Nothofagus dombeyi forest in northern Patagonia on Volcan Osorno in the Vicente Perez Rosales National Park. It is possible that this Brahmaculus species is restricted to the wetter and warmer forests in northern Patagonia, but more specimens are needed to determine the range of the species.

Figures

Figure 5. Brahmaculus osornoensis (PDD 116649) A fresh apothecia (dried apothecia inset) B squash mount, excipulum and hairs in 3 % KOH + Melzer's reagent C squash mount, hairs in water showing encrusting crystals D paraphyses and asci E ascospores. Scale bars: 1 mm (A); 10 µm (B-E).