Ganoderma parvulum Murrill, Bull. Torrey bot. Club 29: 605 (1902).

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

7. Ganoderma parvulum Murrill, Bull. Torrey bot. Club 29: 605 (1902).

Figs 3I , 9

≡ Fomes parvulus (Murrill) Sacc. & D. Sacc, Syll. Fung. (Abellini). 17: 123 (1905). Type: NICARAGUA, s.d., C. L. Smith s.n. (type: NYBG 985699!).

= Fomes stipitatus Murrill, Bull. Torrey Bot. Club. 30(4): 229 (1903).

≡ Ganoderma stipitatum (Murrill) Murrill, N. Amer. Fl. (New York) 9(2): 122 (1908). Type: NICARAGUA, 1891, Smith C. L. and Shimek B. s.n. (isotype: NY 985679!).

= Fomes subamboinensis Henn., Hedwigia 43(3): 175 (1904) [MB148868].

≡ Ganoderma subamboinense (Henn.) Bazzalo & J.E. Wright ex Moncalvo & Ryvarden, Synopsis Fungorum 11: 82 (1997).

≡ Ganoderma subamboinense var. subamboinense Bazzalo & J.E. Wright (invalid name).

Description.

Basidiocarps annual, stipitate or with a contracted base, woody, solitary or gregarious, applanate to sulcate, irregular to tuberculate, dimidiate to semicircular, 1.5-8 × 0.7-12.3 × 0.5-2 cm; pileus surface laccate or dull, sulcate, crustose, rugulose to glabrous, vinaceous-brown, vinaceous-black, reddish-brown, brownish-black to yellowish-brown, yellowish-red, margin obtuse, vinaceous-brown, reddish-brown, yellowish-red or yellowish-brown, azonate or with yellowish-brown, brownish-black or reddish-brown zones; context duplex, corky, yellowish-brown to beige, becoming darker, vinaceous-brown to reddish-brown, just above the tubes, with two horizontal bands of melanoid substances, sometimes more like deposits than bands, that originate from the base of the stipe, 2-17 mm thick, becoming dark with KOH; pore surface reddish-brown, vinaceous-brown to yellowish-brown, pores circular, 4-7 per mm; tube layers reddish-brown, brownish-black to yellowish-brown, sometimes whitish within; tubes layers simple to stratified, 1-8 mm thick. Stipe glabrous, sulcate or smooth, laccate or dull, lateral, vinaceous brown, vinaceous-black, vinaceous-red, yellowish-brown or brownish-black, 2.3-8.5 × 0.5-3 × 0.4-3 cm. Hyphal system dimitic; contextual generative hyphae inconspicuous, thin or thick-walled, with clamps, 4 µm; skeletal hyphae thick-walled, brown, aseptate, occasionally branched, 3-7 µm in diam. Cuticular cells from the pileus cylindrical to clavate, yellowish, with granulations and amyloid reaction on Melzer’s Reagent in the apical part, thick-walled, nodulose, 31-66 × 5-10 µm (20-40 × 6-10 µm, Ryvarden (2004)). Basidia not observed. Basidiospores ovoid, truncate at the distal end; with two walls, connected by inter-wall pillars, brown or subhyaline, negative in Melzer’s Reagent, 7-10 × 5-7 µm. Chlamydospores few, in the context, thick-walled, yellowish-brown, slightly ornamented, 6-8 × 5.5-6 µm; in pure culture, abundant, thick-walled, brown, ornamented, with longitudinal ridges, 8-10 × 6-9 µm.

Descriptions and illustrations.

Ryvarden (2000, 2004, as G. stipitatum ), Cabarroi-Hernández et al. (2019).

Substrata.

On hardwood logs.

Altitudinal distribution.

Lowlands to highlands. In Costa Rica, this species is more common in the lowlands.

Geographic distribution.

Widespread in the Neotropics, reported from south-eastern USA (Florida) to Brazil.

Specimens examined.

Costa Rica. Alajuela; Poás, Carrillos, 10°1'41.6"N, 84°16'55.1"W, 800 m elev., M. Mata GA-10 (USJ109860, sequences ITSOQ845473, LSUOQ835189). Cartago; Turrialba, La Amistad Caribe, Parque Nacional Barbilla, sendero El Felino, 9°58'19.7"N, 83°27'50.8"W, 700-800 m elev., 07 Aug 2002, R. Valladares 1372 (CR3537817). Guanacaste: Liberia, Parque Nacional Guanacaste, Estación Biológica Cacao, 10°55'35.4"N, 85°28'2.4"W, 1700 m elev., 4 Jul 1994, J. Carranza JCV 28-94 ( USJ53210 ); Sector Colorado, camino a pozas del Río Colorado, 10°40'3.10"N, 85°29'12.6"W, 150 m elev., 3 Sep 2021, M. Mardones, M. Mata, J. Carranza GA-37 (USJ109790); 10°40'6.9"N, 85°29'9.01"W, 150 m elev., GA-35 (USJ109791); 10°40'5.21"N, 85°28'56.4"W, 150 m elev., GA-38 (USJ109792); GA-46 (USJ109861, sequences ITSOQ845474, LSUOQ835190). Heredia: Santo Domingo, San Luis, carretera Braulio Carrillo, 9°58'28.2"N, 84°4'4.3"W, 1200 m elev., on Casuarina sp., 04 Jul 2018, M. Mardones GA-04 (USJ109789, sequences ITSOQ845470, LSUOQ835187, TEF OR022012 ); 9°58'28.2"N, 84°4'4.3"W, 1200 m elev., 04 Aug 2018, M. Mardones GA-08 (USJ109714, sequence ITSOQ845471). Sarapiquí, Puerto Viejo, Estación Biológica La Selva (OET), 10°26'0.30"N, 84°0'16.8"W, 100 m elev., 23 Jun 2022, J. Carranza JCV 3-16 (USJ109702). Limón: Cantón Central, Reserva Biológica Hitoy Cerere, Sendero Tepezcuintle, 9°40'19.9"N, 83°01'42.9"W, 0-100 m elev., 9 Nov 2002, R. Valladares 1636 (CR3557538); Sixaola, 9°30'25.4"N, 82°36'43.59"W, 10 m elev., 24 Jun 1988, A. Conejo 32-88 ( USJ28075 ). Puntarenas: Coto Brus, San Vito, Área de Conservación La Amistad Pacífico, Zona Protectora Las Tablas, Estación Biológica Las Alturas, sendero a Cerro Echandi, 8°56'56.9"N, 82°49'59.0"W, 1500-1600 m elev., 12 Nov 1999, E. Navarro 1439 (CR1546847). Golfito, Reserva de Vida Silvestre Golfito, sendero La Lechería, 8°39'17.3"N, 83°13'4.8"W, 100-200 m elev., 13 Jun 2003, E. Fletes 5248 (CR3727447); 8°39'18.1"N, 83°13'8.8"W, 100-200 m elev., 09 Feb 1991, J. Carranza JCV 4-91 ( USJ33128 ); Sector el Tajo, 8°40'11.2"N, 83°11'55.4"W, 0-100 m elev., 05 Sep 2004, E. Fletes 6566 (CR3881862). Osa, Parque Nacional Corcovado, Rio Madrigal, quebrada Ceniza, 8°26'53.9"N, 83°30'54.6"W, 200-300 m elev., 19 Mar 2003, E. Fletes 4943 (CR3700175); Parque Nacional Corcovado, Estación Los Patos, márgenes del Rio Rincón, 8°34'27.7"N, 83°30'27.6"W, 80 m elev., 21 Aug 1999, E. Fletes 631 (CR1546789); Parque Nacional Corcovado, orillas del río Pavón, 8°31'1.03"N, 83°35'52.8"W, 100-200 m elev., 27 Feb 2005, E. Fletes 7239 (CR3932787); Parque Nacional Corcovado, Estación Sirena, márgenes del río Sirena, 8°28'51.12"N, 83°35'51.2"W, 0-100 m elev., 09 Apr 2003, E. Fletes 4999 (CR3717017); sendero Guanacaste, 8°28'56.0"N, 83°35'21.72"W, 10 m elev., 25 Mar 1999, E. Fletes 266 (CR1546586); Sendero Sirena, 8°28'47.8"N, 83°35'46.9"W, 0-30 m elev., on log, 07 Jul 2022, J. Carranza, M. Mardones, E. Fletes GA-56 (USJ109780, sequences ITSOQ845475, LSUOQ835191); Parque Nacional Corcovado, Estación La Leona, Sendero Paraíso, 8°26'49.1"N, 83°31'21.6"W, 0-30 m elev., on log, 10 Sep 2009, J. Carranza JCV 114-09 ( USJ83245 ); Reserva Biológica Isla del Caño, sendero al mirador, 8°42'21.1"N, 83°53'27.0"W, 0-100 m elev., 20 Aug 2003, E. Navarro 7005 (CR3752717). San José: Montes de Oca, San Pedro, Campus UCR, frente a facultad de Medicina, 9°56'19.2"N, 84°3'0.2"W, 1100 m elev., on log of Casuarina sp., 04 Oct 1999, J. Carranza JCV 2-99 ( USJ71256 ); 9°56'19.2"N, 84°3'0.2"W, 1100 m elev., 02 Oct 2018, M. Mardones GA-09 (USJ109788, sequences ITSOQ845472, LSUOQ835188); frente a la Facultad de Educación, on log, Nov 1999, A. Ruiz s.n ( USJ71255 ); on log, 09 Aug 2011, J. De León, O. Morales, R. Doss JDL 15-2011 (USJ109685).

Specimens of other species examined for comparison.

Ganoderma pulverulentum . Grenada. Sep 1905, W.E. Broadway s.n. (lectotype, NYBG 985708). Ganoderma sessile . USA. New York: Westchester Co., White Plains, May 1897, L. M. Underwood s.n. (type, NYBG 985711). Ganoderma sessiliforme . Mexico. Morelos: Cuernavaca, Gardens, and Barrancas within 3 miles of Cuernavaca, 24 Dec 1909, W. A. Murrill 392 (type, NYBG 985713).

Discussion.

Ganoderma parvulum is characterised by a laterally stipitate basidiocarp and light-coloured context on the upper part and darker close to the tubes, with melanoid encrustations or bands running from the base of the stipe (like the ones found on G. curtisii ). According to Cabarroi-Hernández et al. (2019), ornamented chlamydospores in the context and pure culture is the only morphological characteristic distinguishing G. Ganoderma parvulum from G. mexicanum s.l. Few chlamydospores were observed in G. parvulum vouchers collected in Costa Rica and, in some specimens, were totally absent. However, in pure cultures of specimens GA-08 and GA-09, ornamented chlamydospores were numerous (Fig. 9E ). In Carranza and Ruiz-Boyer (2001), chlamydospores of the culture JCV 2-99 (as G. lucidum ) were reported as round to ovoid or elongate and 14-21 × 11-19 µm.

Cabarroi-Hernández et al. (2019) reported much larger basidiospores (11-16 × 9-14.5 µm) than those observed in the Costa Rican specimens (7-10 × 5-7 µm). The size of the basidiospores reported by Ryvarden (2000), as G. stipitatum , (7-9.5 × 5-6.5 µm) and Torres-Torres et al. (2012, 8-9 × 6-6.8 µm) agree with our observations. The type specimen under the name Fomes stipitatus Murr. collected on dead wood in Nicaragua was examined. It had very much deteriorated, with only a small portion of the pileus and context. No spores were observed, but it had cuticular cells amyloid at the apex, 19.5-24 × 6.8 µm and two melanoid bands are observed in the context. Murrill (1915) reported for G. parvulum spores 5 × 4 µm and for G. stipitatum 3.5 × 5 µm, both measurements were very small compared with those described by the above authors. The spores observed in the specimen of G. perzonatum considered by Steyaert (1980) as G. parvulum are larger, 7.7-9.4(-10) × 6-7.7(-8.5) µm, but closer to the ones found on the Costa Rican specimens and the ones reported by other researchers.

Several sequences of specimens of G. parvulum are represented in our dataset (GA-04, GA-08, GA-09, GA-10, GA-46, GA-56). The sequences are grouped in clade IV with good support (1/73) within a subclade containing sequences from several neotropical specimens labelled as G. parvulum , G. mexicanum , G. stipitatum , G. weberianum and G. subamboinense . Ganoderma subamboinense var. subamboinense and G. stipitatum , neotropical species within the Ganoderma weberianum - Ganoderma resinaceum complex, were recently synonymised under Ganoderma parvulum ( Cabarroi-Hernández et al. 2019).

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 9. Ganoderma parvulum A basidiocarp (Fletes 266) B context tissue (Fletes 6566) C cuticular cells (Fletes 266) D basidiospores (Fletes 6566) E chlamydospores (GA- 09). Scale bars: 10 µm (C); 20 µm (D, E).