Aroramyces guanajuatensis Pena-Ramirez , Guevara-Guerrero, Z. W. Ge & Martinez-Gonzalez

Pena-Ramirez, Rafael, Ge, Zai-Wei, Gaitan-Hernandez, Rigoberto, Martinez-Gonzalez, Cesar Ramiro & Guevara-Guerrero, Gonzalo, 2019, A novel sequestrate species from Mexico: Aroramyces guanajuatensis sp. nov. (Hysterangiaceae, Hysterangiales), MycoKeys 61, pp. 27-37 : 27

Aroramyces guanajuatensis Pena-Ramirez, Guevara-Guerrero, Z. W. Ge & Martinez-Gonzalez sp. nov. Figures 2 , 3 , 4

Type.

MEXICO. State of Guanajuato, municipality of Guanajuato, Cuenca de la Esperanza Protected Natural Area, 7 November. 2016 Peña-Ramírez 108 (Holotype: ITCV 1613).

Diagnosis.

Aroramyces guanajuatensis is characterized by a peridium 167-240 µm thick, of cotton-like hyphae, up to 170 µm, long, variably structured mesocutis, yellowish subcutis, spores with irregular and inflated utricle.

Etymology.

" guanajuatensis " in reference to the site (Guanajuato state) where the new taxon was discovered.

Description.

Basidiome 4.4 –17×3.9–13.5×3.2– 11.2 mm, globose or subglobose to irregular, sometimes compressed when growing together. Peridial surface white, pale brown, fibrillose or tomentose, often with cotton-like patches of white hyphae encompassing some debris soil, stones, leaves, and roots. Peridium Separable and fragile, exposing portions of the gleba. <0.5 mm thick, mostly hyaline, outer portion pale brown, with a dark ring next to the gleba. Gleba brown, trama gelatinized, locules irregularly shaped, columella dendroid, translucent gray. Odor fungoid; taste not recorded. Basidiomata hard wen dried.

Peridium three layered, 165-240 µm thick. Epicutis 7.5-22.5 µm thick of hyaline to reddish brown, thin-walled, interwoven to repent or erect hyphae, 2-9 µm wide, forming scattered caespitose groups of erect, branched, setal hyphae up to 170 µm long, with abundant crystalline structures adherent on hyphal walls, clamp connections present. Mesocutis 55-105 µm thick, abundant hyaline, isodiametric, globose to subglobose, angular pseudoparenchyma like cells. 4 –35×3– 24 µm, also with some irregularly shaped, interwoven hyphae, 3-11 µm wide. walls 1-2 µm µm wide, clamp connection absent. Subcutis 22.5-95 µm thick, of interwoven prostrate hyphae, 3-4 µm broad, with scattered large pseudoparenchyma like cells up to 37.5 × 30 µm, clamp connection absent.

Trama of hyaline, interwoven hyphae 4 µm wide, embedded in a gelatinized matrix, clamp connections present.

Basidia fusoid to clavate, hyaline, 14-48 × 9-12 µm, mean = 32.5 × 10.3 µm, wall 1 µm thick. Basidiospores ellipsoid to broadly ellipsoid, symmetrical, hyaline to pale brown, slightly reddish in KOH, pale brown in mass, excluding utricle 9-13 × 6-7 µm long, mean = 11 × 6.1 µm, Q range = 1.5-2.17, Q mean = 1.8; with utricle 12-17 × 7-10 µm long, mean = 14.47 × 8.27 µm, Q = 1.5-2.13, mean = 1.76. Ornamentation of irregular crest contained within an inflated utricle, hilar appendage in cross-section appears rectangular, 1-3 × 4-6 µm, mean = 1.97 × 5.2 µm. Apex obtuse. Utricle inflated up to 3 µm from spore wall, mean = 1.43 µm, occasionally the utricle is asymmetrically inflated.

Distribution, habit and ecology.

MEXICO, state of Guanajuato. Cuenca de la Esperanza Protected Natural Area. Hypogeous, under Quercus spp. at 2530 m. 21°03.87'N, 101°13.193'W. October to December. The March collection was dried in situ.

Additional material examined.

Mexico, state of Guanajuato, Cuenca de la Esperanza Protected Natural Area: 21°04.075'N, 101°13.193'W 2500 m, 26 October 2016, Peña-Ramírez 102, paratype (ITCV 1610). 21°03891'N, 101°13.531'W 2457 m, 5 October 2016, Peña-Ramírez 70 (ITCV 1689). 21°03.891'N, 101°13.533'W, 2464 m, 5 October 2016, Peña-Ramírez 72 (ITCV 1691). 21°03.88'N, 101°13.561'W, 2471 m, 5 October 2016, Peña-Ramírez 75 (ITCV 1694). 21°03.85'N, 101°13.278'W. 2533 m, 19 October 2016 Peña-Ramírez 92 (ITCV 1711). 21°03.741'N, 101°13.461'W. 2500 m, 14 November 2016, Peña-Ramírez 110 (ITCV 1729). 21°03.901'N, 101°13.551'W. 22 December 2016, Peña-Ramírez 119 (ITCV 1738). 21°03.905'N, 101°13.018'W. 2458 m. 22 December 2016, Peña-Ramírez 120 (ITCV 1739). 21°04.045'N, 101°13.018'W. 2508 m, 6 March 2017, Peña-Ramírez 122 (ITCV 1741).

Figures

Figure 2. a-f Aroramyces guanajuatensis (holotype ITCV 1613) a, b basidiome showing the peridial surface c basidiome in cross-section showing glebal surface d cross-section of peridium showing three-layered peridium (1 epicutis, 2 mesocutis, 3 subcutis) at 400 x e-f basidiospore 1000 x f irregular crest contained within an inflated utricle. Scale bars: 0.5 cm (a-c, f), 20 µm (d), 5 µm (e).

Figure 3. Electronic photomicrograph of basidiospores a Aroramyces balanosporus (ITCV 848) and b Aroramyces guanajuatensis (ITCV 1739). Scale bars: 5 µm.

Figure 4. a-f Aroramyces guanajuatensis (holotype ITCV 1613) a-c Cross-section of peridium a epicutis of hyphae postrate cells and angular pseudoparenchyma like mesocutis b arrow head showing postrate cell subcutis c arrow head showing large cell scattered in subcutis d arrow head showing epicutis hyphae with attached crystals e basidia and basidioles f epicutis clamp connection. Scale bar: 10 µm (a-c, e), 25 µm (d), 5 µm (f).