Arktocara ("Platanista gangetica") which inhabits the tropics, making it its closest living relative. Allodelphinidae also included the genera "Allodelphis", "Goedertius", "Ninjadelphis", and "Zarhinocetus". Its discovery further reinforces the theory that the Platanistoidea river dolphins originated in the oceans. Of the characteristics it shared with other platanistoids was a cylindrical projection of the periotic bone in the ear, deeply grooved rostral sutures on the beak, the widening of the cranium, a depression on the roof of the orbit in the eye socket, a smaller exposed palatine bone in the roof of the mouth, an elongated and convex spine in the tympanic bulla
Asystasia gangetica it has become naturalized. Both subspecies of this plant have been introduced to Australia where "A. g. micrantha" is on the National Environmental Alert List and must be reported when found. The original range of the subspecies is unclear, but it is likely that "A. g. gangetica" was limited to Asia, and "A. g. micrantha" was limited to Africa. Ernest Akamine (1947) found that there were no apparent dormancy mechanisms operating in the seeds, which germinated freely 135 days after being expelled from parent plants. Flower production can begin as early as 40 days after germination, with seed development beginning