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Page number:266 
Remarks (internal):Leucocoprinus cretaceus is easily recognized by its fleshy white basidiomata covered by floccose squamules that are easily removed when touched and by a fusoid stipe inflated toward the base. This species is related to L. squamulosus (Mont.) Pegler from Guyana and Lesser Antilles with similar basidiospores but which lacks an annulus and an inflated stipe base (Pegler 1983, Dennis 1952, Wartchow et al. 2008).
Dennis (1952, 1970) and Pegler (1977, 1983, 1986) identified tropical species with a white basidioma and pileus covered by concolorous floccose squamules as Leucocoprinus cepistipes (Sowerby) Pat. However, Candusso & Lanzoni (1990) and Vellinga (2001) considered L. cepistipes a separate species based on the ochraceus to pale brown squamules covering the pileus surface (Candusso & Lanzoni 1990, Wartchow et al. 2008, Gimenes 2007). Vellinga (2001), Gimenes (2007), and Rother & Borges da Silveira (2009) explain these conflicting species concepts.
Description type:Non-original description 
Description:Leucocoprinus cretaceus (Bull.) Locq., Bull. Mens. Soc. Linn. 14: 93 (1945). Figs 1-5
≡ Agaricus cretaceus Bull., Herb. Fr. 8: tab. 374 (1788).
Pileus 27-75 mm diam., at first ovoid then convex to broadly conical, umbonate in maturity, white (1.A1), covered by easily removed, granular floccose, white squamules, conical to pyramidal on the umbo; margin entire, sulcate. Lamellae white, crowded, free, membranous, 2-4 mm wide, with lamellulae; margin entire. Stipe 50-90 x 3-7 mm, central, cylindrical, becoming inflated fusoid towards the base, 15-30 x 8-15 mm, white, glabrescent, fistulose, with a covering of floccose squamules from the base to the annulus. Annulus present, attached to the upper part of the stipe, simple, membranous, white, evanescent. Context white, thin. Spore print white.
Basidiospores 6.8-10 x 5-6.6 µm (8.5 ± 0.8 x 5.7 ± 0.4 µm); Q = 1.2-1.7 µm; Qm = 1.5, n = 60, ellipsoid, hyaline, smooth, thick-walled, walls 0.6-0.7 µm, with an obvious germ pore, dextrinoid, metachromatic, cyanophilic. Basidia 18-30 x 7-11 µm, claviform, with 4 sterigmata. Pseudoparaphyses 11-18 x 6-10 µm, claviform. Pleurocystidia absent. Cheilocystidia 38.3-46.6 x 8-16(-20) µm, narrowly clavate, lageniform to ventricose, thin-walled, hyaline. Hymenophoral trama regular, hyphae 3.6-8 µm, with smooth, thin walls; inamyloid. Pileipellis made up of hyaline hyphae with smooth walls and cylindric terminal elements with excrescences, branched in different shapes (H, T and Y), 24-45 x 7.5-15 µm. Stipitipellis a cutis of narrowly cylindrical, 2-7 µm broad hyphae. Clamp connections absent.
Habitat (of Argentinean collections) — Solitary or gregarious. On bark of living gymnosperms (Araucaria angustifolia) and unidentified dicotyledonous trees in subtropical forest.
Distribution - Leucoagaricus cretaceus is distributed in tropical regions and adjacent temperate regions in North America and Europe (Vellinga 2001, Birkebak 2010). It has been recorded from Africa, Asia, Europe, North America, and South America (Brazil: Gimenes 2007, Meijer 2006, Rother & Borges da Silveira 2009, Sobestiansky 2005, Wartchow et al. 2008). This is the first record of L. cretaceus in Argentina (Misiones and Corrientes Provinces).
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