Morphological and chemical characteristics of the species Chenopodium ambrosioides L. (erva-de-santa-maria) e Coronopus didymus (L.) Sm (mastruço) has been here described. It's observed that problems of identification among them only are due once considering the continental dimensions of Brazil.
Chenopodium ambrosioides L. (erva-de-santa-maria); Coronopus didymus (L.) Sm (mastruço); santa maria herb; mentruz; menstruço