Appropriate legislation based on in-depth ecological evidence is essential for ecosystem conservation. Wetland areas in the Brazilian Cerrado hotspot are facing difficulties in terms of status under environmental law: only those wetlands with the palm Mauritia flexuosa (veredas) are recognized as protected. Comprehensive fieldwork in central-western Brazil (72 50-m transects) coupled with both exploratory and confirmatory analyses showed that communities with (MP) and without (MA) M. flexuosa are similar in terms of the floristics and ecology. The results demonstrate that the analysed wetlands are part of a continuum, in which a gradual replacement of species and community structure occurs without a pattern related to physiognomy. Considering such floristic and structure patterns when legally defining the ecosystem would promote a more comprehensive and realistic view of the ecosystem's characteristics and functions, and result in laws with a stronger scientific support. Conservationists should further examine the lack of consistent separation of plant community attributes between the MP and MA areas, and reconsider the scientific definition of veredas.