This is my new betta! He was sold as a halfmoon, and I realize he is missing a large chunk of this tail... I believe he bit it off on his own while stuck in that tiny petco cup. His fins are semi-translucent and have an iridescent look to them when the light hits him right. He has a black band down from his gills to under his chin... I think it's just a coloration? If not please, please correct me if it's something I need to worry about and treat.
Sorry for the image size, I can try to fix it if there's a problem.. poor quality as well. Apparently all of our digital cameras in the house are either missing or broken. >.>