The answer is yes and yes. The more commonspecies of angels found at your lfs are Pterophyllum Scalare. There are various strains of these, the one closest to the original wild caught is silver. All the different color strains originate from there. Check out
http
/theangelfishsociety.org/genetics.htm for a good series of articles explaining some of the history behind this.
Besides P. Scalare, there is P. Leopoldi, P. Altum, and P. Dumerili. These are mainly found in the wild, but occasionally breeders get them to work. No marbles, koi, or other varieties with these.
Depending on who you talk to, and how they classify them, there can be somewhere around 6-8 different species. It all can be broken up or lumped together differently depending on the location. For practical purposed, Leopoldi & Dumerili are usually classified together. Many sub groups within these species hybridize, and there is also a situation called species cline, where species gradually change due to changes in geography or climate.