These two are similarly marked and easily confused.
Although D. rufotaenia is less than half the size of ravindra, there are dwarf forms of ravindra which approach the size of rufotaenia.
Moreover there are observations of mating between ravindra and rufotaenia which give rise to intermediates. DRUPD.png
Drupadia Probably a rendition of King Drupada in the Mahabharata, in the generic form of nomenclature.