Cosmarium Corda ex Ralfs (Desmidiaceae) in an urban artificial lake, Paraná, Brazil

Abstract

The aim of this work is the taxonomic survey of species of the genus Cosmarium from Lago Municipal de Cascavel, Paraná. Samples collections were carried out between 2002 to 2003, 2007 and 2008, in the lake littoral zone with phytoplankton net. Eighteen taxa were identified, described and illustrated, which three species, fifteen varieties and one forms a taxonomic. Nine taxa (50%) of total were first cited to the Paraná State: C. denticulatum Borge var.  ovale, C. depressum (Nägeli) Lundell var. elevatum Borge, C. galeritum Nordstedt var. galeritum, C. montrealense Croasdale, C. pseudopyramidatum P. Lundell var. pseudopyramidatum, C. pseudopyramidatum var. maximum Börgesen, C. quadrum Lundell var. minus Nordstedt, C. regnellii Wille var. regnellii e C. variolatum Raciborski var. cataractarum.