Abstract
Lemnoideae are the smallest Angiosperms, Wolffia is the genus with smallest fronds and flowers. Morphological interpretations are difficult and terms used for description are slightly different from those used for other plants. A survey of Lemnoideae was carried out in Paraná between July 2013 and September 2014, the specimens collected were identified and prepared according to special herborization techniques and deposited at UPCB and UNOP herbaria. Six species were found: Landoltia punctata, Lemna minuta, Lemna valdiviana, Spirodela intermedia, Wolffia brasiliensis and Wolffiella oblonga. Typically found in lentic environments, sewage ditches and creeks of the river, in Paraná they have been collected in Tropical Rainforest, Araucaria Forest, semideciduous forest and cerrado remnants.
Key words:
flora of Paraná; Lemna; Spirodela; taxonomy