Agaricales » Stephanosporaceae » Mayamontana

Mayamontana coccolobae

Mayamontana coccolobae Castellano, Trappe & Lodge 2007, in Castellano, et al., Mycotaxon, 100, 289-294 (2007)

Etymology: coccolobae refers to the association of this species with the plant, Coccoloba belizensis.

Diagnosis: Basidiomata beneath loose litter or exposed, attached to the surface of mineral soil, attachment point evident at base where the peridium does not enclose the gleba, when fresh 6-8 mm in diameter, ovoid, bright orange, slightly felty, as dried 2-3 x 2-5 mm, irregularly flattened, subglobose to globose, pale orange tan to orange to bright orange, slightly felty, very wrinkled; gleba when dried friable, pale red-orange to red, when rehydrated in 5% KOH the mediostratum of the trama is often bright red; spores and hyphae partially filling the irregularly rounded locules, 0.1-0.2 mm broad, red-orange leachate apparent when mounted in 5% KOH; columella lacking; odor none; taste not recorded. Peridium 100-125 μm thick, of pale orange, thin-walled, inflated cells and irregularly interwoven to subparallel hyphae (5-10 μm in diam); the tissue near the outer surface encrusted with debris; the tissue near the gleba tends to have more interwoven hyphae than inflated cells, but no clear demarcation of peridial layer boundaries; trama similar in structure to the peridium but more pale to nearly hyaline, of thin-walled cells irregularly inflated, up to 17 x 39 μm, mostly about 15 x 20 mm; subhymenium of hyaline, thin-walled, cells irregularly inflated up to 5mm diam; hymenium a palisade of basidia and basidioles, collapsing soon after spore development and obscured by the mass of spores; cystidia absent; basidia hyaline, thin-walled, subclavate, 25-37 x 7-10 μm, 4-spored; sterigmata 2-6 μm tall, 1-2 μm wide at base, hyaline; clamp connections absent; spores (9-) 10-12 (-14) x (5-) 6.5-7 (-8) μm, asymmetrical, broadly ellipsoid to subglobose, slightly flattened on one side, smooth; utricle uneven, slightly wrinkled, not inflated, giving the spore a roughened to warty appearance, thick walled, up to ±2 μm thick; inner surface of the spore wall appearing uneven, in KOH mostly hyaline but sometimes slightly pale green or yellow singly, in mass pale green-yellow, in Melzers reagent no reaction; spore walls 0.5 μm thick; pedicel distinct, up to 3 μm long and 2 μm wide; the end appearing ragged.

Index Fungorum Number: IF510441

Notes:  Mayamontana is characterized by the small, hyaline, asymmetrical, smooth spores with a roughened utricle and a distinct pedicel, unusual in sequestrate taxa. The spores are similar to those of Sclerogaster in overall appearance but are significantly larger in size and lack the distinct warts of Sclerogaster spores. Basidiome characters are reminiscent of Stephanospora in peridial color, size, texture of the peridium and fruiting habit. We extracted DNA material from M. coccolobae and upon performing a BLAST search using GENCOM it is placed in the Stephanosporaceae (Martin et al. 2004) near Stephanospora caroticolor (Berk.) Pat. (GenBank Accession AJ419224). The characteristics of the basidiome are somewhat similar to species of Stephanospora but basidiomes of Stephanospora species have a yellow peridium and a gray-olive gleba. Mayamontana also differs markedly from all described Stephanospora taxa by the lack of a basal ornamental collar or coronasurrounding the spore base and prominent, wedge-shaped ridges.