Definition on a Corona:  A crown-shaped, funnel-shaped, or trumpet-shaped outgrowth or appendage of the perianth of certain flowers, such as the daffodil, Hoya, or the spider lily. Also called crown. I have added a new section to the website called Hoya Coronas.  I will continue to add species as subpages of the Hoya Corona page as time allows.  Even if you are not scientifically minded, please check it out, as some of these photos will make you look at your Hoyas in an entirely different way.