Species/Subspecies question (Peachfaced) & Longfeathered?

[OoLovebirdieoO]

Agapornis roseicollis is the species and I read that there are 2 subspecies: Agapornis roseicollis catumbella and Agapornis roseicollis roseicollis.

This website says that Agapornis roseicollis roseicollis is an independant race?http://www.agapornidenclub.be/agas_ros1.htm

How can you tell if a lovebird is actually a subspecies? Do they look differently and are there pictures of them?

I've also been looking at Longfeathered Peachfaced after I came across it by accident (I had no idea why my Lovebird Rosey is so big and I eventually came across Longfeathered).
http://share.shutterfly.com/action/welcome?sid=1IbtWzVm4asI8 (old photos)

Im confused as to what a Longfeather is, are they a subspecies or like a mutation. Are they like when people breed dogs (sorry I know this sounds odd) they are the same species but come in different shapes and sizes like breeding to get bigger build like a labrador?

There isn't alot on the internet about these birds and I haven't had much luck in books. I came across some articles and I found this one quite interesting (it's more from a bird show standards perspective). The article says that they shouldn't be bred with normal peachfaced. It's confused me quite a lot.
http://didiermervilde.bestofbreeds.net/didier/salmonesarticle.htm

There are also these if anyones interested in the Longfeather.
http://www.agapornis.be/artikels/doslangbev1.html
http://africanlovebirdsociety.com/genetics/longfeathers/longfeather.html

[linda040899]

I know just enough about Longfeathers to be dangerous but I'm far from an expert on them. They are not a sub-species, but rather, they are a mutation. The reason you don't breed them to normal Peachies is because you would lose the long feather characteristic.

I believe the difference between Rosicollis and Catumbella is size. Catumbella is larger and not seen all that often.

Hope this helps.

[OoLovebirdieoO]

thanks for the reply, it did help. :)