Otista

Otista refers to a genus of freshwater snails within the family Viviparidae. These snails are commonly known as river snails or mystery snails. They are native to freshwater habitats across various continents, including Asia, Africa, and Europe, though their distribution has been influenced by human introduction in some regions. Otista snails are characterized by their round, globose shells, which are typically coiled in a sinistral (left-handed) direction, although some species may exhibit dextral coiling. Their shells can vary in color and size depending on the species.

These snails are aquatic and inhabit slow-moving or still freshwater environments such as rivers, lakes, ponds, and canals. They are often found attached to submerged vegetation or substrate. Otista snails are herbivores or detritivores, feeding on algae, plant matter, and organic debris. They are ovoviviparous, meaning they give birth to live young. This reproductive strategy differentiates them from many other snail species that lay eggs. Otista snails play a role in their ecosystems as grazers and as a food source for other aquatic organisms. Some species are also raised for consumption or kept as aquarium pets, though invasive populations can sometimes cause ecological issues.