Here's a pic of my DT...before he started the tailbiting. :/ His caudal fin is not completely divided into two separate lobes. His more more the "heart" variation...which from what I gather isn't "desirable" but I love him anyway
This is when he was first brought home:
This is the best picture showing his extensive finnage:
And when the fin biting began
At it's worst:
He healed up quickly and let his fins fill back in almost completely. And last week, started it back up again.

AHHH....the downside of the amazingly heavy finnage of the DT.