I think you're expecting to see a "Dracula" style transformation. That doesn't exist (if it did, it would be proof that miracles really happen). It takes a very long time, and a large number of generations, for small but cumulative changes to result in some creature's descendants becoming noticeably a different species. And there's considerably more evidence than "a random tooth or an occasional skull fragment." Someone is feeding you some really out-of-date information.
I would hope you would give me more credit than that. I am NOT asking for a modern onset of trans-mutation. I am asking is there a known species that has been identified as in some stage of that process today?