Oto

Found in large schools, amongst dense vegetation, of creeks, rivers, and streams.
They feed nocturnally on algae and plant material.
South America - Amazon River Basin

A freshwater fish often seen in the aquarium trade, often used as cleaners/algae eaters in the tank.
These fish are able to breathe air and also have suction on their lips so they can move around feeding while being stuck to an object.