Dicranthidium arenarium (Ducke, 1907) is a solitary bee distributed along the Atlantic Forest and Caatinga biomes in Northern Brazil. Although it is often sampled in faunistic inventories, its biology is still poorly known. We therefore studied the biology of D. arenarium to understand and compare the patterns of behavior, seasonality, nidification, and its natural enemies in different biomes where it appears. In order to achieve this goal, trap nests were installed and monitored in areas of Caatinga and Atlantic Forest in Northeastern Brazil over one year. We described, illustrated, and discussed their nest architecture, nesting behavior, mortality rates, and sex ratio. Additionally, the behavior of the Austrostelis appendiculata (Ducke, 1910) in D. arenarium nests was observed and described for the first time, showing a similar pattern to that of the other cleptoparasites lineages of Epanthidiina. Their distribution in distinct biomes, the multivoltine cycle, and the plasticity in the use of cavities showed that D. arenarium is a promising species for conservation and pollination programs in natural, urban, and agricultural environments.