A diverse group of organisms that reside primarily in water bodies, including seas, oceans, rivers, ponds, and lakes. This category encompasses a wide range of creatures such as amphibians, such as toads, and arthropods, which consist of invertebrates with exoskeletons, segmented bodies, and paired jointed appendages. These species have adapted to survive and thrive in water-based environments, and are a crucial part of the aquatic ecosystem.