Search on : Taxa descriptions

 


   
Literature:
 
Page number:321 
Description type:Non-original description 
Description:GANODERMA ZONATUM Murrill, Bull. Torrey bot. cl. 29: 606. 1902; North Amer. F1. 9 (2): 120. 1908.
= G. sulcatum Murr., ibid. 29: 607. 1902; North Amer. F1. 9 (2): 120. 1908 (NY).
Figs. 17-22; 51-56; 59,
Annual, isolated, dimidiate and laterally stipitate, or several pilei imbricate on a common stem, 6-20 x 4,5-20 x 0,5-5 cm. Pileus surface smooth or concentrically sulcate,
usually with 1-3 furrows, the inner one usually deeper, thus exhibiting a wavy appearance, sometimes also radially rugose; laccate, brilliant, central zone reddish brown (P1. 7 1 11) becoming lighter towards the margin with a narrow orange brownish marginal band (Pl. 12 D 11)', often delimited by the external furrow and the margin (Figs. 17, 19-20). Margin sterile, blunt, straight, yellowish whitish (Pl. 11 B 1). Stem concolorous with pileus, laccate, brilliant, 3,5-5 cm long, 2-4 cm wide, vertical,cylindric or depressed. Section 8-10 mm deep at about half the radius, thicker at the base. Cutis thin, black, brilliant. Context brown (P1. 14 C 12), slightly lighter at the surface of pileus, 3-44 mm thick, corky, soft. Dermis of the "hymenodermis"type, composed of the claviform ends of skeletal hyphae arranged in a palisadelike hymenium, 6-11 µm diam., with small lumina, blunt ends and thick, golden walls; dermis 17-33 µm thick (Fig. 62). Hymenophore poroid, tube layer 1-5,5 mm long, slightly lighter than context (P1. 13 C 8), decurrent on stem, concolorous with margin, pores 3-5 per mm, 98-267 µm diam., circular to subangular, greyish to slightly brownish upon maturation (Figs. 18, 21-22); dissepiments 30-89 µm. Hymenium not persistent, composed only of scant basidia, 4-spored, 11-17 x 7-11 µm (Fig. 59). Basidiospores of the "semirugose" type, very characteristic, ellipsoid, long and slender, with truncate apex or, more frequently, rounded, 11-14 x 5-7 µm, perisporium hyaline, smooth and thin, endosporic pillars numerous, reaching the perisporium and slightly rumpling it, thus making it appear slightly rugose; endospore golden and thick (Figs. 51-56). Hyphal system trimitic, with hyaline, thinwalled, clamped generatives, with septa restricted to clamps, sparsely or not at all branched, 2-4 µm diam., present in the growth margin of pileus and dissepiments (Fig. 71). Skeletals of the "arboriform" type, long, with a thick, golden wall, clampless, aseptate, with 2-3 branches of same diam. As mother hyphae at distal end (Fig. 68), 3-6 µm diam., the most abundant in the context and dissepiments. Binding hyphae of the "Bovista" type, clampless, aseptate, of limited growth, heavily branched, generally thinner and lighter than skeletals, 1-3 µm diam., thick-walled, restricted to the context (Figs. 69-70).
Hosts: on dead stem of palm (Butia yatay) and dead wood and roots of living Tipuana tipu.
Distribution: U. S. (Florida, Georgia); ARGENTINA (Corrientes and Entre Rios ).
Material studied: ARGENTINA: Corrientes: Dept°Cosme, Paso de la Patria, leg. Singer, 5.IV.1957 (BAFC 24416 ; Mburucuyd, Estancia Santa Teresa, leg. Pedersen, 29.111.1977 (BAFC 24414). Entre Rios: Parque
Nacional El Palmar, leg. Mercuri, 25.11.1979 (BAFC 2444T-UNITED STATES: Florida leg. Underwood, 1914 (HOLOTYPE NY!); ibid., leg. Lloyd, 1.1897 HOLOTYPE of G.sulcatum Murr., NY!). CUBA: leg. Murrill (BAFC 25601, as G. tuberculosum).
It was not possible to obtain cultures of this species.
According to Murrill, the only differences between G. zonatum and G. sulcatum lie in the pileus surface. Both holotypes were studied in detail, their microscopic features being identical, especially the basidiospores, which are long, slender, ellipsoid, "semirugose" and of the same size. Pores are identical. All this coincides with the Argentine specimens (their spores being very slightly more rugose). We do not agree with Murrill's description in North American Flora, since our measurements of the spores from the holotypes are 11-14 x 5-7 µm and not 8-10 x 4-6 µm as he states, and the pores are 4-5 per mm and not 3-4.
We agree with Steyaert and Overholts that both species are synonyms. The former revised the holotypes in 1962 establish ed their identity, and the latter published them as synonyms but as varieties of P. lucidus Leys.:Fr. under the epithet lucidus var. zonatum (Murr.)Overh. Only interfertility studies will be able to prove whether or not this taxon can be separated from G. lucidum. For the time being we prefer to consider it as separate.
DISCUSSION
According to our studies, the G. lucidum-complex would thus appear to be represented in Argentina by five species, namely, G. lucidum s. str., G. resinaceum (Boud.)Pat., G. zo natum Murr., G. oarstedii (Fr.)Torrend, and G. subamboinense P. Henn. var.laevisporum var. nov. Spegazzini (1926) recorded other species for Argentina, which we have been unable to find in his herbarium, namely G. cupreum, G. sceleton and G. fornicatum. G. platense Speg., whose holotype was studied, resulted another synonym for G. resinaceum. Additional synonyms for this species proved to be G. pulverulentum, G. nitidum and G. subincrustatum. The question of the validity of G. multiplicatum var.vitalii Steyaert, G. lorentzianum Kalchbr., and G. orbiforme Fr. remains pending a thorough study of their respective holotypes.
Since other holotypes and authentic materials of species that have as yet not been found in Argentina were studied, but were recorded from other South American countries, a preliminary general key for the complex has been included in this paper.
The type of dermis is useless for the separation of species, but permits the separation of "complexes" of species, such as in the present case. In this we agree with Steyaert (1972, 1980) and Imazeki (1939); they considered the existence of three or four (Steyaert, 1980) subgenera on this basis. Regarding the hyphal system of basidiome construction, our results confirm those obtained by Hansen (1958).
Cultural studies did not exhibit significative differences and ought to be used with caution. We attempted several methods for germinating spores with the hope of obtaining monosporous cultures in order to verify interfertility patterns, but were unsuccessful. This had been done previously by Merrill (1970) with similar results. We also tried the methods proposed by Aoshima (1953) and Brown (1970) for spores of G. applanatum,but also failed. We did not test Lim's method (1970). Equally unsuccessful were our attempts to obtain monokaryotic mycelia from dikaryotic ones (dedikaryotization). More studies in this line are urgently needed.
 
Taxon name: