Boa confusion.

[Jrich]

I know I purchased a BCI on Sunday but BCI and BCC's look so similar I can't even really tell them apart. Every website I've been to that tries to help distinguish them says something different or contradicts the last website. Some call both red tail boas. Then people say that's a Columbian red tail or an Argentinean red tail or true red tail for the BCC but still refer to BCI as red tail or common boa and then there's hog island boas, please tell me that's a whole other story.
Holy crap I know I got lost in the weeds with the names but it's good to know. One consistent thing I've read so far is that BCI's don't grow as large as BCC's, however I keep coming across pictures of very very large BCI's or BCI's that match up not only size but maturity to BBC's. Or maybe it's people incorrectly identifying the snake?