Leccinum neotropicalis Halling, Kew Bull. 54: 748. 1999.
Pileus (4)58.5(13) cm broad, at first convex, with age becoming plano-convex to plane, dry to moist to slippery (when wet), rugose to rugulose to subrugulose; disc even to uneven (rarely), at first brown to dark brown to dark reddish brown, then remaining brown to dark brown to dark reddish brown; margin subrugulose (rarely), when young brown to dark brown to dark reddish brown, then remaining brown to dark brown to dark reddish brown; surface matted subtomentose to subtomentose to subvelutinous to velutinous; sterile appendiculate flaps absent. Flesh 1020 mm thick, white to pale yellow to pale pink, staining absent; odor mild; taste mild. Hymenophore tubulose, adnexed to depressed to deeply depressed. Tubes 710 mm long, yellow, becoming greenish yellow to olive yellow, unchanging when injured; pores up to 1 mm wide, yellow, unchanging when injured or light cinnamon brown when bruised. Stipe 5.59(11) cm long, 1025 mm wide, equal to subclavate to clavate, dry; upper half when young pruinose to ridged with pallid ridges, yellow, with age pruinose to ridged with pallid ridges, yellow; lower half when young finely scabrous to ridged with pallid ridges, sordid yellow, with age finely scabrous to ridged with pallid ridges, rarely pink or sordid yellow; scabers on upper half when young gray brown, with age gray brown to tan to clay, on lower half when young clay to gray brown to tan, with age gray brown to tan to clay; base white to pale yellow, staining not present. Stipe interior solid; flesh above when young white to yellow, with age white to yellow, staining not present; flesh at base when young white to yellow, with age white to yellow, staining not present. Basal mycelium white to yellow.
Basidiospores dull cinnamon brown, 10.517.5 µm long, 3.84.9 µm wide, mean Q = 2.61, smooth, elongate ellipsoid to fusoid to subfusoid, inamyloid. Basidia 2432 µm long, 812 µm wide, clavate, hyaline, 4 -sterigmate. Hymenial cystidia 3048 µm long, 68 µm wide, thin walled, hyaline, narrowly lageniform to fusoid to subcylindrical, encrusting pigment absent. Tube trama boletoid, hyaline, in KOH yellowish, lateral strata elements 48 µm wide, not gelatinized. Pileipellis hyphae hymeniform, pigment encrustations dextrinoid (at pellis/trama interface); elements 1025 µm wide, cellular to subisodiametric or subelongate (rarely), thin walled, often beneath a gelatinized layer. Pileus trama interwoven, hyaline, inamyloid, with elements up to 20 µm wide, smooth, thin walled. Stipitipellis hyphae vertically oriented, parallel, giving rise to clusters of caulocystidia, up to 60 µm long, 15 µm wide, clavate to subclavate to subfusoid, occasionally with golden yellow contents, with incrusting pigment absent. Stipe trama hyphae parallel, cylindric, hyaline, inamyloid. Clamp connections absent.
Mycorrhizal host: Quercus.
This Leccinum is reminiscent of L. crocipodium as currently outlined by Lannoy and Estades (1995). Recent accounts in North America (Smith, Thiers, and Watling 1967; Smith and Thiers 1971) indicate that it occurs in the United States. However, as circumscribed by those authors, that taxon has a much lighter colored pileus, and perhaps more significantly, the context changes with exposure to a pinkish or salmon to reddish vinaceous and finally blackish. The Costa Rican material is consistently dark brown to dark red brown with immutable flesh.
Cite this publication as: Halling, R. E., G. M. Mueller, and M. J. Dallwitz. 1998 onwards. Leccinum and Phylloporus in Costa Rica: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 13 Decmber 2006. http://www.nybg.org/bsci/res/hall/deltaindex.html. Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993 onwards, 1998) should also be cited (see References).