The Ganges river dolphin has a rectangular, ridgelike dorsal fin and females tend to be larger than males.[9] Ganges river dolphins usually are tan, chocolate brown, dark grey or light blue. They have an elongated, slender snout with sharp and very pointed teeth, similar to most river dolphins. The river dolphin has a rounded belly, which, combined with its rectangular dorsal fin, makes it look particularly stocky in build compared to other dolphins. Their flippers and tail flukes are large and broad.[10] They have a large melon head used for echolocation, because they cannot see well. Their eyes are usually small due to the cloudy water.[9] Ganges river dolphins are usually 2.2–2.6 meters long (7–8 ft). The oldest recorded animal was a 28-year-old male, 199 cm in length, although they are estimated to live up to 30 years old.
The Ganges river dolphin split from the Indus river dolphin during the Pleistocene, around 550,000 years ago.[1] The earliest fossil identified as belonging to the species is only 12,000 years old.
