It was suggested that this be moved to it's own post so it can be easily found later on.
Very good idea, Jarie, I agree completely.
A quickie look at some of the most visible differences.
Brugmansia Group I
There are three main species. B. aurea, B. versicolor, and B. suaveolens.
B. aurea:
The flowers usually nod or point straight out (sometimes upward slightly.)
The flower portion that sticks out of the calyx is usually shorter.
This one is where long tendrils and serrated leaf edges come from.
Rothkirch is a pure B. aurea, a wild-collected specimen of this species.
B. versicolor
Versicolor flowers hang straight down and have moderate length tendrils.
This species has the longest flowers and long, skinny buds.
The calyx only has 1 split where the flower comes out.
Ecuador Pink is a pure B. versicolor, wild-collected.
B. suaveolens
The flowers of these nod downward and have very short tendrils.
The calyx is generally shorter and doesn't cover the narrow part of the flower tube.
Golfito is a pure B. suaveolens, wild-collected.
There really aren't very many known pure species available, but there are more than just these three. I had a list saved, but I can't remember them all right now.
After the pure species, we have naturally occuring hybrids. That basically means a cross between a pure species and another pure species, originally found growing wild, Mother Nature made.
First, B. x. insignis.
This is a cross between a pure B. suaveolens and a pure B. versicolor that has then been crossed back to a pure B. suaveolens.
The flowers are very much like a B. suaveolens, but with longer flowers and longer tendrils.
Some examples of x. insignis style, your NOID pink, most likely, Insignis Gold, Tropical Sunset. I'm not sure which would be a wild-collected one of these.
And second, B. x. candida.
This is a cross between a pure B. aurea and a pure B. versicolor.
These typically are closer to a versicolor, but with aurea influences. If you cross one back to an aurea, it will usually be more like an aurea, same if you cross it back to a versicolor it'll look more like a versicolor. I'm not sure which would be a wild-collected one of these either.
This one is the only one that will produce doubles/triples, they are classified as Brugmansia x. candida flore plena.
You also get some nice fuzzy leaves in the candidas, a personal favorite.
For most of the named hybrids that are available, they can't accurately be labeled as any of these. Most of them aren't either pure or pure x pure. But by the visible characteristics you can usually get a pretty good guess as to which genes are dominating.
Examples:
B. aurea, B. versicolor, B. suaveolens
Perhaps more can even be added to this? Leaves, flower buds, seed pods, they all vary, we could make this a really detailed, full of information, kind of thing. Maybe even move beyond the basics? And I think it would be really great if someone into Group II Brugs would add them to this as well.
Lynne
USDA 9b, Heat 10
Bradenton, Florida
Current Kanji: hana (flower)
Hope we can have more of these very informative postings from so many of you experienced and knowledgable folks. Looking forward to becoming more enlightened!! LOL 
Gloria
