A new species of Claudopus (Entolomataceae ? Basidiomycota) from the Argentinean Atlantic Forest

NIVEIRO, NICOLÁS; BARONI TIMOTHY J.; ALBERTÓ, EDGARDO

Lima

Congreso; IX Congreso Latinoamericano de Micología; 2017

Asociación Latinoamericana de Micología

Claudopus Gillet is characterized by its crepidotoid or pleurotoid basidiomata, with absent or reduced lateral stipe and distinctly angular spores in all views. Some authors consider Claudopus as an independent genus, meanwhile others mycologists treated Claudopus as a section within Entoloma, a current and popular trend. Worldwide, species of Claudous are scarce with approximately 20 species described to date. From South America, only six species of Claudopus were described: C. tympanifer Horak, C. cyaneum Murrill, both from Brazil, C. depluens var. macrosporus Dennis, from Venezuela and C. chilensis Speg. from Chile. In Argentina, we recorded two Claudopus species described by Spegazzini: C. argentinus Speg. and C. argentinensis Speg., but both species were currently transferred to Rhodocybe and Entoloma respectively. The aim of this paper is to propose, describe and illustrate a new species of Claudopus recently found in the Atlantic forest in northeastern Argentina. The specimens studied were collected by the authors in protected areas and deposited in CTES Mycological Herbarium. These specimens were documented both macro and macroscopically. For microscopic characters, a light microscopy (LM) and a scanning electron microscopy (SEM) were used. The species here described is distinguished from other species of Claudopus by the darker basidiomata colorations and it is characterized by the black to dark gray with some brownish gray pileus surface colors and pinkish brown to brownish gray, ventricose lamellae, lack of a stipe, heterodiametric spores, 8.5?11.5 x 5.5?7.5 µm in size, and lack of any type of cystidia. Claudopus byssisedus, the most phenetically related species and with a wide distribution in temperate and colder regions, but has a paler coloration, narrower lamellae and slightly larger spores. This new species is somewhat reminiscent of members of the Entoloma rusticoides group because of the colors of the pileus and lamellae, however members of that group have well developed stipes and isodiametric basidiospores.