Tetradesmus lagerheimii is a green algae species that forms colonies (coenobia) composed of four spherical to ovoid cells with smooth surfaces. These cells are relatively small, typically ranging from a few to several tens of micrometers in diameter, and are supported by firm cell walls. Each cell contains chloroplasts, usually positioned along the cell wall and potentially containing pyrenoids for photosynthesis, with a centrally located nucleus. Reproduction occurs through asexual cell division within the coenobium, facilitating colony growth. Tetradesmus lagerheimii thrives in freshwater habitats such as ponds, lakes, and slow-moving streams, where it contributes to the diversity and productivity of phytoplankton communities.