Floristic composition of domestic units on the Brazil-Paraguay border: an ethnoecological approach Human cultures have particular and differentiated ways of perceiving, identifying, classifying and, above all, interacting with the natural environment. Ethnobiology, a sub-area of Ethnoscience is the basis of Ethnobotany and Ethnoecology, which present studies on the knowledge of a cultural group on botany and ecology, therefore, on human interactions with the natural environment. The knowledge obtained / generated constitutes an important basis in the definition of strategies that allow the biological and cultural conservation. These studies are also relevant to know the mechanisms used by human populations in their interaction with the environment. Based on these principles, the present study aimed to ethnoecologically record the relationship of the human being with the vegetal composition of the domestic unit, considering cultural, social, biological and ecological aspects. In this way, it is intended to contribute to the conservation of ethno-species diversity in the Brazil-Paraguay border region, in the municipality of Ponta Porã, in the state of Mato Grosso do Sul, during 2016 and 2017. For this purpose, it was observed which plants are available and which are recognized as resources, and how these are used. Data collection procedures involved methods associated with Anthropology and Classical Botany, both suitable for ethnoecological studies. Sixty interviews were conducted with the representatives of each household in the 15 selected city areas. These participants stated that they were responsible for the whole care or for parts of the household. According to the conception of the residents the definition of domestic unit is directly related to the space in which activities related to family leisure are developed, being cited by the interviewees as the place reserved to take tereré-a typical drinkto spend time, where the children play, practice various activities. It is also used for the cultivation of vegetables obtained through the purchase and exchange of seedlings, thus evidencing the contribution of the homegardens to the relations of neighbors and relatives. In this study, the plant component of the 60 participating urban households, known and used by residents, corresponds to 219 species, 82 botanical families, 1560 individuals. Participants know and cultivate vegetables in domestic units belonging to five categories of use: food, medicinal, shading, mystical / religious and ornamental. Of all the species mentioned, 17 were considered by the interviewees to be toxic. These plants are thus considered toxic, because they cause some adverse effect to the organism when in contact or ingestion, and can even lead to death, being the symptoms quite variable from one individual to another. The studied domestic units are organized according to their size and structure and have different potentials, as they also fulfill different specific functions, according to the purposes and characteristics of each inhabit...