Complex sentence: The family is small, consisting of seven species in the genus "Toxotes"; which typically inhabit brackish waters of estuaries and mangroves, but can also be found in the open ocean, as well as far upstream in fresh water.
Split into simpler sentences: The family is small, consisting of seven species in a single genus "Toxotes". The seven species typically inhabit brackish waters of estuaries and mangroves, but can also be found in the open ocean, as well as far upstream in fresh water.