If you have purchased it this spring, I would go back and look at the various tags still in pots at the nursery where you bought it. Or use process of elimination to figure out what it might be when comparing to your list. Or just enjoy the flowers and don't worry about the name. You can figure out how to prune it based on when it blooms in future years. Regardless of type it will be encouraged to grow healthy roots if you hard prune it the first spring or two.

There are a couple of reasons it is difficult to ID photos of young plants. Color is difficult to judge on-line since both the camera and the computer monitor can alter it. Small plants in pots from the nursery may be blooming earlier than they typically would, having been forced, and the flowers on young plants may not be the size or petal count of mature plants. Also, IME clematis at Lowe's can be mislabeled, perhaps from the nursery and perhaps from customers pulling out the tag to look at and then not returning them to the correct pot. And there are lots of purple clematis, though perhaps fewer that also have the reddish brown anthers as on yours.

If you want to try to ID yourself, you can go to the Clematis on the Web database and do a search. Just fill in the things you know and leave the rest blank.

This clem is at least a year old - tag must have gotten lost over the winter as I am good about labeling things. I went through my whole list and looked at the possibilities - Lady Betty Balfour was the only one that seemed logical - but if the blooms are different on a young plant - I might have better luck as it ages. I have, for the last couple of years, trimmed all mine back to facilitate more root growth. At any rate - it is lovely and if I don't find the name, will enjoy it anyway. Was just hoping someone would see it and say - aha! I have some unknown roses and daylilies too.......doesn't lessen the enjoyment!