 A 1947 study found plants of "R. emodi" a chromosome count of 2"n"=22, but the same study found plants labelled as "R. australe" to be 2"n"=44.It is possible that this karyotypic diversity indicates the existence of one or more cryptic species, because the polyploid forms would essentially be reproductively isolated.Native to India, Myanmar, Nepal, Pakistan, Bhutan, and Sikkim.