Hi, Steve, glad to hear from you and welcome to ATP. There's been lots of research going on with Rhipsalis in Brazil and Germany the past few years. rhipsalis.com has some links to some interesting research and scientific articles that help distinguish the different varieties.
Lynn, sorry I missed your post and question. I don't have an exact count of my rhipsalis, but probably have 30 or more varieties, but most are still small. I lost several this past year during the winter months, but that is typical due to the very low humidity indoors here. I don't have the space to keep a lot of larger specimens, so small size works best.
