The karyotypes of five Brazilian species of Echinodorus; E. bolivianus, E. grandiflorus, E. longipetalus, E. macrophyllus and E. tenellus (Alismataceae); were studied using C-banding, CMA(3)/DAPI banding and fluorescence in situ hybridization with a 45S rDNA probe. There were few differences in the G-C rich regions of the five species, but marked differences were seen in the number and position of C-bands, A-T rich regions and 45S rDNA sites. Overall, these characteristics were species-specific, with the exception of E. bolivianus and E. tenellus, which were highly similar in all of the karyotypic characteristics studied.25741671119127