From the Greek rheos - flow, stream and taxis - location.

Rheotaxis - movement of fish fry against the current, in larvae - body positioning towards the flow.

It is characteristic of fish, is also inherent in some lower plants (plasmodia of myxomycetes or slime molds), unicellular animals, although at present the presence of rheotaxis is proved only on the example of plasmodia of myxomycetes, as they move along the substrate against the water flow, but towards its source. It is believed that cells are oriented by shear stress, possibly involving gravitational forces. For example, planaria swim against the direction of fluid flow. Some species of fish (moustache, chub, etc.), higher crustaceans (amphipods, mysids, etc.) have rheotaxis.