Ganoderma mexicurtisii Cabarroi-Hernández, Decock, Amalfi, M. Torres & Guzm.-Dáv., 2025

Cabarroi-Hernández, Milay, Decock, Cony, Guzmán-Dávalos, Laura, Torres-Torres, Mabel Gisela, Robledo, Gerardo Lucio, Villalobos-Arámbula, Alma Rosa, Martínez-Velázquez, Zurizadai, Ramírez-Cruz, Virginia & Amalfi, Mario, 2025, The Ganoderma curtisii lineage (Basidiomycota, Polyporaceae) in the Neotropics: Ganoderma mexicurtisii sp. nov. from pine-oak forests in Mexico, IMA Fungus 16, pp. e 154828-e 154828 : e154828-

Ganoderma mexicurtisii Cabarroi-Hernández, Decock, Amalfi, M. Torres & Guzm.-Dáv. sp. nov.

Fig. 2

Diagnosis.

Ganoderma mexicurtisii is similar to G. curtisii but distinguished by a generally paler yellowish pileus and clavate cuticular cells, apically branched or with protuberances and spheroid diverticula, slightly to strongly amyloid.

Type.

MEXICO, JALISCO: • Municipality of Mixtlán , taken from the exhibition in the Mushroom Fair in Mixtlán, oak-pine forest, on roots, 18 Jul 2021, L. Guzmán-Dávalos 12340 (holotype: IBUG- 15648 !, isotypes: BR!, NY!), sequences ITS rDNA, rpb 2, and tef 1 (Gp 29) .

Description.

Basidiome stipitate, solitary, sometimes scattered, rarely two from the same base, spongy when fresh, light in weight. Pileus dimidiate, conchate in pole view, rarely circular, convex or applanate in section, projecting 4–9 cm, 5–15 cm wide; pileal surface laccate to dull, smooth, rugose or with concentric deep sulcations, pale yellow (4 A 3, 4 A 6), deep yellow (4 A 8), yellowish – orange (5 B 8), yellow – brown (5 C 8) to brown – violet (11 F 8), generally darker near the union with the stipe, peeling off very easily, exposing the context; margin regular to slightly lobulated, sometimes incurved, white to pale yellow (4 A 3) to light brown (7 E 8). Stipe mostly mesopodal, occasionally pleuropodal, mainly orthopleuropodal, occasionally plagiopleuropodal, or rarely dorsally lateral, cylindrical, straight or bended to tortuous, 2.5–27 × 1–5 cm, uniform, slightly swollen or attenuate at the base, laccate, brown – violet (11 F 8), golden – yellow (4 A 4, 5 B 8), concolor with the pileus to pale yellow (3 A 3). Pore surface pale yellow (2 A 3) when fresh, pale yellow (3 A 3) to golden – yellow (4 A 4, 5 B 8) on drying, staining brown (6 D 8) when bruised; pores angular, occasionally round, 2–4 (– 5) per mm; dissepiments conspicuous. Context duplex, with a spongy consistency, slightly fibrous texture, 0.7–2 (– 4) cm thick, pale to light orange (5 A 3–5 A 4) next to the crust, and brown – sienna (6 D 7) to rarely yellow – brown (6 F 8) above the tubes, with few to several (up to 4) longitudinal, pale to brown, resinous bands, azonate. Tubes 3–10 mm deep, without stratification, rarely stratified, brown – violet (8 E 4).

Hyphal system dimitic; generative hyphae 3–3.5 μm diam., septate, with clamp connections, thin – walled, hyaline to yellowish, difficult to observe; skeleto – binding hyphae with an arboriform pattern, pale golden – yellow, tortuous, sometimes with some protuberances, golden – yellow, thick – walled, composed of a basal stalk arising from a clamp, with apical processes, the branches gradually tapering from 3.2–4 μm wide at primary processes to 2.4–3.2 μm wide at thin – walled apices in an area above the tubes, and from 4–6 μm wide at primary processes to 3–4 μm wide at the thin – walled apices with some moniliform hyphae (7–11 µm diam.) below the crust. Pileipellis a crustohymeniderm; cuticular cells mostly clavate, lumen widely open, in the lighter zone of the pileus, thin – walled, 0–3 protuberances, with several or non spheroid diverticula, slightly amyloid to almost black in mass, and in the darker zone of the pileus clavate, with no or ≤ 4 irregular long branches, rarely the clavate form lost, thick – walled, strongly amyloid, 43–96 × 7.2–16.5 µm. Basidia pyriform, with four sterigmata, ~ 20 × 7.2 μm. Basidiospores oblong to ellipsoid, with an apical conical umbo often collapsed, then appearing truncate, double – walled, the inner wall thick, pale yellowish, with thick, subfree pillars, (9.2 –) 10.5–12.8 (– 13.5) × 5.5–8.0 µm, Q = 1.44–1.88. Chlamydospores not observed.

Habitat and distribution.

Solitary to scattered, growing on soil (roots of trees, mainly Quercus ), in oak-pine forest and a relict mixed forest of Fagus grandifolia var. mexicana and Pinus . Known from Mexico (Hidalgo, Jalisco, Morelos, State of Mexico).

Etymology.

Prefix “mexi” refers to Mexico and “curtisii” refers to its resemblance to Ganoderma curtisii.

Specimens examined

(all as paratypes of Ganoderma mexicurtisii ). MEXICO, HIDALGO: • Municipality of Tenango de Doria, Temapa , 20°37'47"N, 98°12'49"W, 20 Nov 1969, J. Gimate 152 – A ( ENCB) ; • Municipality of Zacualtipan , 20°37'47"N, 98°36'58"W, 2000 m a. s. l., relictual mixed Fagus grandifolia var. mexicana and Pinus forest, emerging from leaf-litter, 22 Jul 2009, C. Decock MX – 09–20 (living strain MUCL 52280 = CBS 152593 ) . JALISCO • Municipality of Bolaños, Crucero Miguelón , 21°55'17.7"N, 103°52'13.9"W, pine-oak forest, 30 Aug 2024, M. Cabarroi 20 ( IBUG) ; • Municipality of Colotlán, 16.5 km west of Colotlán to Carrizal , 22°5'1.23"N, 103°12'24.8"W, 2 Aug 2004, M. G. Torres-Torres 541 ( IBUG) ; • Municipality of Cuautitlán de García Barragán, brecha Las Joyas-Manantlán , 19°33'10"N, 103°46'19.99"W, 23 Sep 1983, A. G. Valenzuela s. n. ( IBUG) ; • Municipality of Cuautla, Tierras Blancas , 20°15'39"N, 103°30'20.99"W, 2200 m a. s. l., pine-oak forest, 16 Jul 2017, L. Guzmán-Dávalos 11569 ( IBUG), sequence Gp 30 ; • 29 Jul 2018, L. Guzmán-Dávalos 11735 ( IBUG), sequence Gp 38 ; • Municipality of Cuquío, Las Cruces , 21°1'25"N, 102°53'20"W, 12 Oct 1980, J. Mejía-Jimenez s. n. ( IBUG) ; • Municipality of Etzatlán, Etzatlán-Mesa Colorada road, near El Amparo , 20°42'3"N, 103°55'1.99"W, 1600–1800 m a. s. l., oak-pine forest, 4 Sep 1997, L. Guzmán-Dávalos 6742 ( IBUG) ; • Municipality of Mascota, 800 m after La Campana, km 83.5 Guadalajara-Mascota road , 20°42'3"N, 103°55'1.99"W, pine-oak forest, 17 Aug 1998, L. Guzmán-Dávalos 7447 ; • 16 Jul 2022, L. Guzmán-Dávalos 12404 ( IBUG) ; • Municipality of Mazamitla, 5 km west of Mazamitla, Los Cazos , 19°54'7"N, 102°57'57.99"W, 15 Feb 1994, H. Orozco 5 ( IBUG) ; • 5 km from La Manzanilla de La Paz to Mazamitla , 19°57'14"N, 102°49'59"W, pine-oak forest, 6 Oct 1984, L. Guzmán-Dávalos 1723 ( IBUG) ; • Municipality of Mezquitic, La Cebolleta , pine-oak forest, on Quercus sp. , 15 Aug 1997, L. Villaseñor-Ibarra 282 ( IBUG) ; • Municipality of Mixtlán, Los Perones , 20°26'45.2"N, 104°21'53.99"W, 28 Jul 2018, M. X. Haro-Luna 394 ( IBUG), sequence Gp 37 ; • Mesa Colorada , 20°28'43.31"N, 104°22'29.43"W, oak-pine forest, 27 Jul 2018, O. Castro-Jauregui 365 ( IBUG), sequence Gp 36 ; • 19 Jul 2023, on stump of Pinus sp. , M. Cabarroi 12 ( IBUG), sequence Sc 389 ; • Municipality of Tecolotlán, Sierra de Quila, km 17.5 Tecolotlán-Quila road , 20°18'14"N, 103°57'3.99"W, M. L. Fierros 494 – A ( IBUG) ; • Municipality of Tequila, Tequila volcano, km 8 of the road to the microwave station , 20°47'31"N, 102°8'45.99"W, oak-pine forest, 30 Jul 1986, J. A. Pérez de la Rosa s. n. ( IBUG) ; • km 12 of the road to the microwave station , oak-pine forest, 28 Jul 2017, L. Guzmán-Dávalos 11586 ( IBUG), sequence Gp 31 ; • 18 Aug 2018, L. Guzmán-Dávalos 11754 ( IBUG), sequence Gp 39 ; • Municipality of Puerto Vallarta, km 31–32 of the Mascota-Puerto Vallarta road , 20°43'21.47"N, 104°52'30.18"W, 10 Sep 2005, P. G. Castañeda 5 ( IBUG) ; • Municipality of Zapopan, Huaxtla, on the side of the road to Cuisillos , on Quercus root, Jun 2024, S. Mata s. n. ( IBUG) ; • Bosque La Primavera, 3 km SE of La Primavera town , 20°39'11.65"N, 103°32'24.50"W, oak-pine forest, 20 Oct 1983, L. Guzmán-Dávalos 1277 ( IBUG) ; • aprox. 8 km from Mariano Otero Avenue , 20°36'16.54"N, 103°32'26.60"W, oak-pine forest, 20 Jul 2004, M. G. Torres-Torres 526 ( IBUG) ; • Bosque La Primavera, entrada por ejido Emiliano Zapata , 20°41'57.75"N, 103°37'56.92"W, 14 Jul 2013, oak forest, M. Hererra 1564 ( IBUG) ; • Bosque La Primavera , 20°41'53.4"N, 103°34'34.7"W, oak-pine forest, 4 Aug 2023, R. Betancourt 89 ; • Bosque del Centinela, corner of Avenue Bosques del Centinela with the street Bosque de Nayarit , 20°45'48.84"N, 103°22'30.25"W, induced oak-pine forest with eucalyptus, casuarina, and castor oil plant, 7 Jul 2018, O. Castro-Jauregui 146 ( IBUG), sequence Gp 32 . MORELOS • Municipality of Tepoztlán, 5 km west of Tepoztlán, near the highway to Cuautla , 18°59'45.98"N, 99°9'40.85"W, 3 Sep 1967, M. Frias Neve 18 ( ENCB) . STATE OF MEXICO • Municipality of Texcoco, Tetzcotzinco Archaeological Zone, on the way to Conjunto Norte , 19°29'50.55"N, 98°49'9.85"W, on Quercus root, 14 Nov 2024, M. Cabarroi 21 ( IBUG) .

Specimens of Ganoderma curtisii examined.

CUBA, PINAR DEL RÍO • Guanahacabibes península, Municipio Sandino, finca del guarda forestal, 1 km from Cayuco , oak forest, on Quercus cubana stump, 28 Sep 2005, C. Decock CU – 05–224 ( MUCL 47086 , living strain MUCL 47086) (Fig. 3 ); • C. Decock CU – 05–225 ( MUCL 47087 ); • C. Decock CU – 05–227 ( MUCL 47088 , living strain MUCL 47088). USA, NORTH CAROLINA • Chapel Hill , Nov 1923, Coker s. n. ( RLS. 63. K. 59 & K. 58), isoneotypus at BR!, fragm.); • Forsyth, Winstom-Salem , in yard, 30 Sep 1934, Schallert s. n. (F); GEORGIA • Thomas, Thomasville , 19 Jul 1947, Field s. n. (F); LOUISIANA • Calcasieu, Lake Prien , on the ground in pine woods, 30 Oct 1984, Drouet s. n. (F).

Specimens of Ganoderma ravenelii examined.

USA, SOUTH CAROLINA • Aiken, on the ground, s. data, Ravenel 2936 (K, holotype!); FLORIDA • Columbia, Camp O’Lena State Park , s. data, Dybas s. n. (F).

Figures

Figure 2. Ganoderma mexicurtisii. A – I L. Guzmán-Dávalos 12340 (IBUG, holotype), A orthopleuropodal basidiome, B duplex context with longitudinal resinous bands (arrow), C cuticular cells from the paler pileal surface with vesicles (arrow), D – E cuticular cells from the darker pileal surface with some apical diverticles (arrow), F moniliform hyphae below the crust, G skeleto – binding hyphae with an arboriform pattern, H – I basidiospore with subfree pillars. J – O M. Cabarroi 12, J plagiopleuropodal basidiome, K cuticular cells from the paler pileal surface with vesicles (arrows), L clavate cuticular cells from the daker pileal zone, with lumen widely open (arrow), M moniliform hyphae below the crust, N – O basidiospore with subfree pillars. P R. Betancourt 89, cuticular cells from the paler pileal surface with vesicles (arrow). Scale bars: 2 cm (A, B); 20 µm (C, D); 10 µm (E, F, G, K, L, P); 5 µm (H – I, M – O); 1 cm (J). Photo A Laura Guzmán-Dávalos, B – P Milay Cabarroi-Hernández.

Figure 3. Ganoderma curtisii, C. Decock CU – 05–224 (MUCL 47086). A Ortho- to plagiopleuropodal basidiome, B duplex context with a resinous band (arrow), C clavate cuticular cells, with lumen widely open, D cuticular cells with occasionally apical branches (arrow) and protuberances (arrow), E – F basidiospore with subfree pillars. Scale bars: 4 cm (A); 1 cm (B); 10 µm (C, D). Photos A – C, E, F Milay Cabarroi-Hernández, D Cony Decock.