English: A spherical water flea (Chydorus sphaericus) photographed under a microscope using a 10x objective. The specimen was collected in March 2022 from a pond in the city of Rakvere, Estonia. This is one of the most common benthic water flea species in the Holarctic region. The image shows the species' characteristic spherical body shape and transparent carapace through which the yellowish body interior is visible. While previously considered a cosmopolitan species, it is now known to be a species complex consisting of several cryptic forms. The specimen was photographed against a black background, which excellently highlights the texture of the semi-transparent body surface. The lighting technique used was reflected light from a photographic speedlight flash, which particularly emphasizes the surface structures and patterns. The image was created using focus stacking technique, which ensures great depth of field throughout the subject.