Stephanospora mayana de la Fuente, Garcia-Jimenez , Guevara-Guerrero & Oros-Ortega

Fuente, Javier Isaac de la, Guevara-Guerrero, Gonzalo, ros-Ortega, Ivan, Romeo Sanchez-Zavalegui,, ordova-Lara, Ivan & arcia-Jimenez, Jesus, 2019, Stephanosporamayana (Stephanosporaceae, Russulales), a new sequestrate fungus from Yucatan Peninsula, Mexico, MycoKeys 48, pp. 115-124 : 119-121

Stephanospora mayana de la Fuente, Garcia-Jimenez, Guevara-Guerrero & Oros-Ortega sp. nov. Figure 3 a–f

Holotype.

Mexico: Campeche State, Calakmul Municipality, Blasillo town, 18°31'N, 88°18'W, 11 December 2017, de la Fuente (JF-397-ITCV), GenBank: MK033630.

Diagnosis.

Stephanospora mayana can be distinguished by the yellowish net-like pileus, the variable spore size (8.0-17.0 × 6.0-11.0 µm), thin pileus (21.0-40.0 µm) and the ecological association to lowland forest and pine savanna with H. campechianum , G. floribundum , C. diversifolia , M. brownei , and P. caribaea .

Etymology.

Named mayana in reference to the Mayan zone where this species was found.

Description.

Basidiomata hypogeous to subhypogeous, scattered, 3.0-15 × 2.0-6.0 mm, globose to subglobose, without rizomorphs or stipe. Pileus yellowish to slightly orange (5A6-30A3-6), bruising pale orange when touched, wet to dry, sometimes net-like, dehiscent, showing locules inside. Hymenophore brittle, grayish (5C4), with empty rounded to angular locules, reaching 0.5 mm long, sometimes with white short and slender hyphae projecting from pileus to locules, trama sometimes orange (5A7-5B7), odour and taste strongly fruity.

Pileus 21.0-40.0 µm thick, composed of loosely interwoven, slender to inflated hyphae, 1.7-4.2 µm in diameter, orange to pale orange-yellow in KOH, thin-walled. Hymenophoral trama irregular, 62.0-100.0 µm wide, composed of irregular, globose, isodiametric and compacted hyphae, 13.5-26.3 µm in diameter, hyaline to slightly yellowish in KOH, thin-walled. Basidia 24.2-30.5 × 9.5-11.1 µm, clavate to subclavate, hyaline in KOH, guttulate, 2-spored, with long sterigmata, reaching 7 µm long, thin-walled, collapsing after basidiospore development. Basidiospores (8.0-) 10.0-16.0 (-17.0) × (6.0-) 8.5-10.5 (-11.0) µm (L = 12.10, W = 9.31, Q = 1.30, N = 90) ellipsoid to subglobose, with truncate to acute spines projecting 2.0 µm long, forming ridges reaching 3.5 µm high, sometimes coalescing, with a complete to partial corona 4.0-6.0 × 1.0-2.5 µm long, sometimes with 2-4 projecting spines, 1.5 µm long, with hilar appendage conspicuous, reaching 3 µm long, bright yellowish in KOH, orange in Meltzer reagent, with greenish to yellowish cell wall, 1.5-2.0 µm thick. Hyphae from the locules hyaline, 3.0-5.0 µm diameter, thin-walled. Clamp-connections absent in all tissues.

Distribution.

Known from the Mexican states of Campeche and Quintana Roo where it is associated to lowland forest and pine savanna under G. floribundum , H. campechianum , M. brownei , and P. caribaea .

Additional material examined.

Mexico, Quintana Roo, Othón Pompeyo Blanco municipality, Santa Elena Town, 18°30'N, 88°23'W, 07 October 2017, de la Fuente and Sánchez-Zavalegui 327 (Paratype); State of Campeche, Calakmul municipality, Xnohá town, 17°53'N, 89°10'W, 30 November 2017, de la Fuente 387 (paratype); Blasillo town, 18°31'N, 88°18'W, growing on abandoned termite mounds, 09 June 2018, de la Fuente 405 (paratype). (All in ITCV.)