Ganoderma amazonense Weir, A pathological survey of the para rubber tree (Hevea brasiliensis Muell . Arg.) in the Amazon Valley: 12 (1926).

Mardones, Melissa, Carranza-Velazquez, Julieta, Mata-Hidalgo, Milagro, Amador-Fernandez, Xaviera & Urbina, Hector, 2023, Taxonomy and phylogeny of the genus Ganoderma (Polyporales, Basidiomycota) in Costa Rica, MycoKeys 100, pp. 5-47 : 5

1. Ganoderma amazonense Weir, A pathological survey of the para rubber tree (Hevea brasiliensis Muell. Arg.) in the Amazon Valley: 12 (1926).

Figs 3A , 4

Type.

Brazil. Amazonas: Cocal Grande , Para, on Hevea brasiliensis (Willd. ex A.Juss.) Müll.Arg., 20 Aug 1923, James R. Weir. Pathological & Mycol. s.n. (lectotype: BPI62043 !) .

Description.

Basidiocarps perennial, pileate, stipitate, sessile or with a contracted lateral base, corky to woody, solitary, applanate, irregular to tuberculate, 8.5 × 11 × 1 cm; pileus surface sulcate, glabrous, dull, brownish-grey to reddish-brown azonate or with zones close to the margin, margin obtuse, yellowish-brown; context yellowish-white, without resinous deposits or with fine discontinue light brown horizontal bands; pore surface pinkish-brown to yellowish-brown, pores circular 4-6 per mm; tube layer pinkish-brown to yellowish-brown, simple, up to 20 mm thick. Stipe concolour with the pileus surface, up to 5 cm long. Hyphal system dimitic; contextual generative hyphae hyaline, thin-walled, with clamps, 2-5 µm in diam., difficult to observe; skeletal hyphae thick-walled, yellowish-brown, aseptate, 3-5 µm in diam., occasionally branched. Cuticular cells from the pileus absent. Basidia not observed. Basidiospores ovoid to ellipsoid, truncate at the distal end; with two walls, connected by inter-wall pillars, hyaline to yellowish-brown, negative in Melzer’s Reagent, 8-10 × 6-7 µm. Chlamydospores not observed.

Descriptions and illustrations.

Weir (1926), Furtado (1967), Steyaert (1980), Gottlieb and Wright (1999a), Ryvarden (2004), Torres-Torres et al. (2012).

Substrata.

On hardwood logs.

Altitudinal distribution.

Lowlands.

Geographic distribution.

G. amazonense is reported in the Caribbean (Jamaica and Puerto Rico) and Central and South America (Costa Rica, Honduras and Brazil). Reports in West and Central Africa ( Steyaert 1980) need further confirmation.

Specimens examined.

Costa Rica. Alajuela: Los Chiles, Reserva Nacional de Vida Silvestre Cano Negro , 10°53'6.71"N, 84°47'28.27"W, 30 m elev., 03 Aug 1991, A. Ruiz-Boyer 7-91 ( USJ36351 ). Upala, Bijagua, Albergue Heliconias, 10°43'21.05"N, 85°2'30.47"W, 500 m elev., on log, 12 Jul 2001, L. Ryvarden 43716 (CR3802379). Guanacaste : Liberia, Parque Nacional Santa Rosa , sector Bosque Húmedo, 10°50'57.49"N, 85°36'57.89"W, 300 m elev., on log, 24 Oct 1996, I. Lindblad 2144.2 (CR3131819). Limón: Cantón Central, Reserva Biológica Hitoy Cerere, Sendero Tepezcuintle, 9°40'19.97"N, 83°01'42.96"W, 100 m elev., on log, 23 Jul 2003, E. Navarro 6843 (CR3727415). Puntarenas: Garabito, Jacó, Sector Garabú, Finca Quebrada Bonita, 9°38'22.81"N, 84°38'40.81"W, 100 m elev., on log, 24 Nov 2008, E. Navarro 10912 (CR4188987); Osa, Parque Nacional Piedras Blancas, Estación Rio Bonito , Sendero Tacho, 9°38'22.81"N, 84°38'40.81"W, 100 m elev., on log, 14 Mar 2003, E. Fletes 4933 (CR3700169); Osa, Parque Nacional Corcovado, Estación Sirena, Sendero Espaveles, 8°28'57.75"N, 83°35'28.87"W, 0-10 m elev., on log, 14 Sep 2001, E. Fletes 2847 (CR3756152); 8°28'59.54"N, 83°35'29.69"W, 0-10 m elev., 14 Jul 2021, J. Carranza, M. Mardones, E. Fletes GA-30 (USJ109778); Sendero Sirena, 8°28'56.01"N, 83°35'49.16"W, 0-30 m elev., on log, 06 Jul 2022, J. Carranza, M. Mardones, E. Fletes GA-54 (USJ109779, sequence ITSOQ845454) .

Discussion.

Ganoderma amazonense was described by Weir (1926) as a new species from the Amazonas (Brazil) decaying the roots of Hevea spp. It is characterised by the dull-brown, non-laccate pileus surface, the pale context and the small, light yellow basidiospores. The basidiospores of the specimens from Costa Rica examined in this study are ellipsoid, echinulate and truncate and measure 8-10 × 6-7 µm that agree with measurements reported by Welti and Courtecuisse (2010) and Torres-Torres et al. (2012). However, slightly smaller basidiospores have been observed in the type specimen (6-9.35 × 4-6 µm) and in descriptions by Gottlieb and Wright (1999a), Ryvarden (2004) and Gomes-Silva et al. (2011). All the specimens of G. amazonense examined in this study were collected in lowlands.

The G. amazonense sequence (GA-54) was placed in our phylogeny as a sister lineage of clade VI with moderate support in the BI analysis (0.78). Our sequence constitutes the first molecular record for this species deposited in GenBank. More sequences from additional molecular markers are needed to confirm the species’ evolutionary relationships with other Ganoderma species, but its position as a separate lineage within the genus is confirmed.

Figures

Figure 3. In-situ photos of basidiocarps of Ganoderma spp. in Costa Rica A G. amazonense (GA- 30) B G. applanatum (GA- 54) C G. australe (GA- 58) D G. cf. chocoense (GA- 03) E, F G. curtisii (JCV 128 - 10) G G. ecuadorense (MMG- 181) H G. oerstedii (Saenz 2049) I G. parvulum (GA- 09). Scale bars: 20 cm (A, H); 3 cm (B, C); 1 cm (D, E, I).

Figure 4. Ganoderma amazonense A basidiocarp pileus (Fletes 2847) B pore surface (Fletes 2847) C context tissue (Navarro 6843) D basidiospores (Fletes 4933). Scale bar: 10 µm (D).