Ganoderma australe (Fr.) Pat., Bull. Soc. mycol. Fr. 5(2,3): 65 (1889).

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

2. Ganoderma australe (Fr.) Pat., Bull. Soc. mycol. Fr. 5(2,3): 65 (1889).

Figs 3C , 5

≡ Polyporus australis Fr., Elench. fung. 1: 108 (1828).

Type.

An island in Pacific Ocean, on log, s.d., s.n. (type lost) .

Description.

Basidiocarps perennial, sessile or with a contracted lateral base, dimidiate, woody, solitary, applanate to ungulate, irregular to tuberculate, 1.6-21.2 × 1.5-32 × 0.3-5.1 cm; pileus surface crustose, rugulose, sulcate, glabrous, dull, greyish-brown, yellowish-brown, reddish-brown to brownish-black, margin obtuse, yellowish-brown to pinkish-brown, azonate or with brownish-black, reddish-brown or yellowish-brown zones; context corky, vinaceous, purple-brown or yellowish-brown, with horizontal bands of melanoid substances, 1-30 mm thick, becoming dark with KOH; pore surface pinkish-brown to yellowish-brown, pores circular, 3-5 per mm; tube layers concolorous with context or yellowish-brown, sometimes whitish within, tubes simple to stratified, up to 0.5-25 mm thick. Hyphal system dimitic or trimitic; contextual generative hyphae inconspicuous, thin-walled, with clamps, hyaline, 1.5-3 µm diam.; skeletal hyphae thick-walled, yellowish-brown, aseptate, up to 6 µm in diam., occasionally branched; binding hyphae thin-walled, 1-2 µm in diam. Cuticular cells from the pileus: absent. Basidia difficult to find. Basidiospores ovoid, truncate at the distal end; with two walls, connected by inter-wall pillars, yellowish-brown, negative in Melzer’s Reagent, 7-12 × 5-8 µm. Chlamydospores not observed.

Descriptions and illustrations.

Furtado (1967), Ruiz-Boyer (1998), Ryvarden (2004), Welti and Courtecuisse (2010).

Substrata.

Dead-standing hardwood trees, stumps or logs.

Altitudinal distribution.

Lowlands to highlands.

Geographic distribution.

Pantropical, common in tropical America.

Specimens examined.

Costa Rica. Alajuela: Arenal, Parque Nacional Arenal, sendero Pilón, 10°27'39.29"N, 84°43'51.83"W, 600-700 m elev., 15 Jul 2001, A. Ruiz 521 (CR3802311); Poás, Parque Nacional Volcán Poás, Sendero hacia el Bosque del Nino , 10°7'3.27"N, 84°14'36.88"W, 2500-2600 m elev., 27 Jun 2007, E. Navarro 10184 (CR4089856); San Carlos, Pocosol, Finca Latite, 10°23'26.51"N, 84°35'49.69"W, 110 m elev., 29 May 2002, J. Carranza JCV 13-02 ( USJ72910 ). Cartago: Jimenez, Pejibaye, Refugio de Vida Silvestre El Copal , 9°47'6.90"N, 83°45'7.77"W, 650 m elev., 26 Apr 2006, E. Navarro 9620 (CR4014312). Guanacaste: La Cruz, Parque Nacional Guanacaste, Estación Biológica Pitilla, camino a la Esperanza, 10°59'28.61"N, 85°25'33.17"W, 700-800 m elev., 23 Mar 1997, C. Cano 1012 (CR1544454) ; Liberia, Parque Nacional Rincón de la Vieja, Estación San Cristóbal, Sendero La Danta , 10°46'31.27"N, 85°21'0.51"W, 600-700 m elev., 28 Sep 1996, C. Cano 615 ( CR144376 ); Sector Santa María, Los Naranjales, 10°46'53.11"N, 85°19'1.38"W, 800-900 m elev., 05 Dec 1997, C. Cano 1237 (CR3495780). Heredia: Sarapiquí, La Virgen, Estacion Biologica La Selva , 10°25'56.52"N, 84°0'13.96"W, 40 m elev., on log, 06 Nov 2016, J. Carranza JCV 2-16 (USJ109687). Limón, Cantón Central, Reserva Veragua, Sendero Los Valientes, 9°55'40.63"N, 83°11'28.53"W, 200-300 m elev., 26 Jun 2009, E. Navarro 11165 (CR4222697); Reserva Biológica Hitoy Cerere, Sendero Tepezcuintle, 9°40'19.97"N, 83°01'42.96"W, 0-100 m elev., 19 Sep 2001, R. Valladares 536 (CR3464661). Pococí, Colorado, Tortuguero, Reserva Biologica del Bosque Lluvioso , 10°26'58.96"N, 83°30'25.19"W, 300-400 m elev., 29 Jan 2004, E. Alvarado 111 (CR3802764). Puntarenas: Cantón Central, Parque Nacional Isla del Coco, orillas del Río Genio, 5°30'15.64"N, 87°4'32.05"W, 0-100 m elev., 04 Jun 2005, E. Fletes 7607 (CR3976554). Coto Brus, San Vito, Parque Nacional La Amistad , Zona Protegida Las Tablas, Fila Chiquizá, 8°55'34.40"N, 82°46'00.950"W, 1500-1600 m elev., 18 Feb 2003, E. Fletes 4870 (CR3575822); Finca Cafrosa, Pizote, 8°54'15.82"N, 82°47'21.22"W, 1400-1500 m elev., 28 Nov 1998, E. Navarro 520 (CR4109271). Osa, Puerto Escondido, Playa Colibrí, 8°39'36.96"N, 83°26'12.46"W, 0-100 m elev., 5 Nov 2006, E. Alvarado 367 (CR4044781); Parque Nacional Piedras Blancas, Estación Rio Bonito , sendero a San Josecito, 8°43'16.18"N, 83°12'14.64"W, 400 m elev., 18 Apr 1999, E. Fletes 341 (CR1546010); Karate, Finca Exótica, 8°26'29.64"N, 83°27'15.39"W, 0-10 m elev., 11 Aug 2019, M. Mata JCV 4-19 (USJ109489); Parque Nacional Corcovado, Estación San Pedrillo, Sendero Llorona, 8°29'1.96"N, 83°35'30.31"W, 10-100 m elev., 16 Feb 2000, E. Fletes 1219 (CR3097854); Sector Sirena, Sendero Espaveles, 8°29'3.30"N, 83°35'30.64"W, 0-100 m elev., 08 Feb 2003, E. Fletes 4860 (CR3575815); 8°28'46.91"N, 83°35'22.30"W, 0-100 m elev., 01 Jun 2012, J. Carranza JCV 310-12 (USJ109694); Sendero Ollas-Sirena, 8°29'5.14"N, 83°35'24.33"W, 0-100 m elev., 01 Jun 2012, J. Carranza JCV 42-12 (USJ109489); Sector Sirena, sendero a Rio Pavo , 8°30' 23.51"N, 83°35'19.34"W, 0-100 m elev., 25 Mar 2003, E. Fletes 1403 (CR1547383); Sendero Espaveles a sendero la Olla, 8°29'4.60"N, 83°35'22.49"W, 0-30 m elev., on log, 07 Jul 2022, J. Carranza, M. Mardones, E. Fletes GA-58 (USJ109795); Sector Aguas Azules, 8°32'35.08"N, 83°34'13.43"W, 0-100 m elev., 12 Mar 2005, E. Fletes 7302 (CR3994940); Estacion La Leona , Sendero Paraíso, 8°26'50.34"N, 83°31'6.19"W, 0-100 m elev., 10 Sep 2009, J. Carranza JCV 25-09 (USJ109489); 8°26'49.55"N, 83°31'8.89"W, 0-100 m elev., 9 Dec 2016, J. Carranza JCV 8-16 (USJ109686); 8°26' 50.79"N, 83°31'14.79"W, 0-100 m elev., 08 Jan 2009, J. Carranza JCV 104-09 (USJ109489). San José, Dota, Reserva Forestal Los Santos, Albergue de Montana Savegre , Sendero Los Robles, 9°33'00.00"N, 83°48'00.0"W, 2400-2500 m elev., 20 Jun 2005, R. Rodríguez 505 (CR3968596); Finca La Neblina , sendero de las Torres a Savegre, 9°37'3.65"N, 83°50'33.3"W, 2500-2600 m elev., 14 Oct 2006, E. Navarro 99712 (CR4043836); Cerro de la Muerte, Km 92.5, Estación Los Nímbulos, sendero en el robledal, 10°25'18.9"N, 84°01'30.6"W, 3100 m elev., 09 Jun 2019, M. Mardones GA-19 (USJ109713, sequences ITSOQ845456, LSUOQ835180). Moravia, Jardínes, 9°58'1.31"N, 84°1'58.2"W, 1300 m elev., 12 Sep 2021, J. Carranza JCV 2-21 (USJ109781) .

Discussion.

Ganoderma australe is a common species in the Tropics that traditionally is considered a cosmopolitan species; but recent studies suggest that G. australe is only present in America and Oceania ( Fryssouli et al. 2020). Macroscopically, the main characteristics of G. australe are tough and sessile basidiocarp with distinct black cuticle, greyish to brown pileus and context with resinous deposits or melanoid bands. Microscopically can be recognised by its cylindrical and hyaline basidiospores.

The Costa Rican specimens have a wide range of colour variations of the pileus and spore sizes. Steyaert, cited by Ryvarden and Johansen (1980), reported spore sizes that range from 6-13 × 4.5-8 µm, while Ruiz Boyer (1998) found 6-8 × 4-6 µm and Ryvarden (2004) mentioned spore sizes of 7-12 × 5-8 µm. The spore sizes of the specimens observed in our study were in the range of the ones mentioned by these authors. Morphologically, amongst the neotropical species of Ganoderma with non-laccate basidiocarps, G. australe and G. applanatum are difficult to differentiate. However, both species can be distinguished by the resinous deposits or melanoid bands present only in the context of G. australe . From the morphological examination of ca. 40 herbarium specimens within the G. applanatum-australe complex in Costa Rica, we determined that most specimens belong to G. australe , with a few occurrences of G. applanatum (see below). There are some specimens of G. australe that do not show resinous deposits or melanoid bands or are very inconspicuous. In these cases, the size of the spores (larger in G. australe than in G. applanatum ) is a criterion to distinguish both species. In other cases, the morphological distinction is complex and molecular characterisation should be used.

Identifying G. australe using the ITS region is challenging since, according to Fryssouli et al. (2020), about 5% of the Ganoderma sequences deposited in GenBank are labelled as G. australe. Still, only 22% of them are correctly tagged. We selected two reference sequences of G. australe from Australia (DHCR411 and DHCR417) to be included in the phylogeny. The sequences JMCR128 and GA-19 grouped with them in a strongly supported subclade (1/98) within clade VI.

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 5. Ganoderma australe A basidiocarp pileus (Fletes 341) B pore surface (GA- 64) C context tissue (Fletes 1403) D basidiospores (Fletes 1403). Scale bar: 10 µm (D).