▁forms ▁of ▁B .   s pha er oc ar pa . ▁It ▁der ives ▁its ▁name ▁from ▁its ▁ 5 0 – 6 5   mm ▁long ▁p ist ils , ▁the ▁longest ▁of ▁any ▁banks ia , ▁and ▁per ian th ▁( 4 9 – 5 5   mm ). ▁The ▁grey ▁old ▁flowers ▁remain ▁on ▁the ▁old ▁con es . ▁ ▁Tax onomy ▁First ▁collected ▁by ▁botan ist ▁Alex ▁George ▁in ▁ 1 9 7 8 , ▁it ▁was ▁officially ▁described ▁in ▁the ▁ 1 9 8 1 ▁revision ▁of ▁the ▁genus ▁B anks ia ▁as ▁a ▁variety ▁of ▁B anks ia ▁s pha er oc ar pa . ▁The ▁specific ▁ep ith et ▁was ▁derived ▁from ▁the ▁An cient ▁Greek ▁words ▁dol ich os ▁" long " ▁and ▁st yl os ▁" p ill ar ", ▁in ▁reference ▁to ▁the ▁long ▁styles . ▁ ▁Botan ist ▁and ▁plant ▁tax onom ist ▁Kevin ▁Th iele ▁anal ys ed ▁the ▁morph omet rics ▁in ▁his ▁cl ad istic ▁paper ▁of ▁ 1 9 9 6 , ▁and ▁announced ▁that ▁the ▁Iron cap ▁banks ia ▁war r anted ▁specific ▁status . ▁He ▁anal ys ed ▁B anks ia ▁mic ran tha ▁as ▁the ▁sister ▁group ▁to ▁the ▁pair ▁of ▁B .   s pha er oc ar pa ▁var . ▁s pha er oc ar pa ▁and ▁B .   s pha er oc ar pa ▁var . ▁ca esia , ▁and ▁noted ▁that ▁the ▁Iron cap ▁banks ia , ▁which ▁was