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Page number:138 
Remarks (internal):The membranous annulus, the presence of chrysocystidia as pleuro-, cheilo- and caulocystidia, and especially the presence of acanthocytes in the type specimens of Pholiota varzeae support its transfer to Stropharia. Singer (1989) included P. varzeae in Pholiota section Albivelatae A.H. Sm. & Hesler; most species of this section have been assigned to Stropharia due the presence of acanthocytes (cf. Norvell & Redhead 2000), an exclusive feature of this genus (Farr 1980). An additional distinguishing feature of the species is its habitat in "várzea" vegetation, growing on palm and wood debris (Singer 1989). Except for only minor differences between the basidiospore size ranges described by Singer (1989) and those reported here, the measurements of the basidia, cystidia, and pileipellis hyphae in the type were slightly larger than those presented by Singer (1989). Singer also did not report cheilocystidia in this species, considering them "veris haud differentiatis". Cheilocystidia as well as pleuro- and caulocystidia were checked in the type specimens and we consider it as chrysocystidia.
Singer (1989) related his Pholiota varzeae to P. cubensis Earle, another species occurring in Brazil (Pegler 1997, Cortez & Silveira 2008). The latter species differs mainly by its more robust habit and absence of chrysocystidia on gill edge and stipitipellis. Norvell & Redhead (2000) recently transferred P. cubensis to Stropharia, renaming it S. earlei Norvell & Redhead. Another similar taxon in Pholiota section Albivelatae is P. apiahyna Speg., which differs from S. varzeae by the fusoid to clavate and mucronate pleurocystidia and the non-chrysocystidioid cheilocystidia. Based on all above-cited features and following the criterion of the presence of acanthocytes as a synapomorphic feature of Stropharia, P. varzeae is considered here as an authentic member of this genus and thus the above new combination is proposed. Stropharia has proved to be a more diverse than previously documented in Brazil. To determine if S. varzeae is in fact restricted to the "várzea" vegetation, as Singer (1984, 1989) stated, will deserve future mycological investigations in Amazon region.
 
Description type:Non-original description 
Description:Stropharia varzeae (Singer) Cortez, comb. nov. Figs. 1-7
Mycobank MB 511191
Basonym: Pholiota varzeae Singer, Fieldiana, Bot. 21: 113, 1989. Pileus 21-30 mm diam, convex and umbonate to subumbonate to finally depressed; rusty (“henna”) with the disc reddish-brown (“mascara” to “Maracaibo”), surface dry; context whitish. Lamellae adnate, close, brownish (“Cuban sand”, “atmosphere” to “kis kilim”), with a conspicuous whitish margin. Stipe 22-46 x 2.5-7.5 mm, central, cylindrical or with a slightly attenuate apex and expanded base; cream to grayish colored, with longitudinal dark brown fibrils; abundant white rhizomorphs and basal mycelium abundant at the base. Veil forming a membranous, slightly grooved and whitish annulus. Spore print “falcon”.
Basidiospores 6-7.5(-8) x 4-4.5(-5) µm, Q= 1.50-1.75(-1.80), Qm= 1.65, n= 30, subellipsoid to ovoid in both face- and side-view, some slightly reniform in profile, smooth and thick-walled, with a reduced germ-pore; yellowish brown in KOH. Basidia 20-27 x 6-7.5 µm, clavate, 4-spored. Pleurocystidia 35-46 x 9.5-13 µm, as chrysocystidia, fusoid or subclavate, with obtuse to rounded apex, thin-walled, with yellowish to greenish contents. Cheilocystidia (24-) 29-38 x (8-)10-13 µm, as chrysocystidia, fusoid to clavate, with a mucronate apex, similar to pleurocystidia, but slightly smaller; thin-walled, with yellowish to greenish contents. Pileipellis a trichodermium, hyphae inflated to subcylindrical, clamped, smooth and thin-walled, hyaline, 11-17(-21) µm diam. Context formed of interwoven, hyaline, thin-walled, and clamped hyphae, 8-16 µm diam. Gill trama regular, composed of hyaline, thin-walled, cylindrical to inflated hyphae, 6-9(-11) µm diam. Stipitipellis composed of hyaline, non-gelatinized, filamentous, smooth and thin-walled hyphae, 4-6.5 µm diam. Caulocystidia 29-47 x 9-12 µm, as chrysocystidia, mainly clavate or some fusoid, similar to the pleurocystidia, abundant on the stipe apex. Acanthocytes numerous, observed only on rhizomorphs' surface. Clamp connections present.
Habitat: gregarious on decayed palm and dicotyledonous wood in tropical flooded forest (“várzea” vegetation).
Examined specimen: Brazil. Amazonas: Paraná do Januacá, near to Santa Luzia, Lago do Castanho, in “várzea” vegetation, 23.V.1980, Singer B 12177 (F 1030768 - holotype).
 
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