I have a few plants with different names that look the same. In my garden rectifolia Chionea looks just like rectifolia Nikai and Rohdeifolia. None of these names are registered. But in the MyHosta database there is a reference to a registered hosta called Ginbuchi Tachi where is states "Japanese name for H. rectifolia 'Chionea'?". In Chris's comment section of the hosta Silver Star he mentions:
Comments: This sport of Hosta rectifolia is known as Hosta 'Ginbuchi Tachi' in Japan but has been renamed Hosta 'Silver Star' in the US to distinguish it from the registered plant of Hosta 'Ginbuchi Tachi' which differs significantly from the hosta we are selling.
Hosta Registry - not registered
MyHostas - http://myhostas.be/db/hostas/Chionea
Hosta Library - http://www.hostalibrary.org/r/rectifoliac.html
Other cross-references:
MyHosta Database reference noting "Japanese name for H. rectifolia 'Chionea'?"
http://myhostas.be/db/view/Ginbuchi+Tachi
http://myhostas.be/db/view/Rohdeifolia
http://hostaregistrar.org/detail.php?id=2525&Variety=Ginbuchi%20Tachi
MyHosta Database reference about Nakai - "Probably the same as rectifolia 'Chionea'."
http://www.myhostas.be/db/hostas/rectifolia+%27Nakai%27
And calling rectifolia Nakai a "species".
Here they are in my garden. The flowers are the same also. I will post them next.