Not too often, as far as I know.
Honestly I don't and will probably never understand why some Varanids are classed the way they are only to be re-evaluated by someone else with a different opinion some time down the road.
I'm really not sure to what spec's Varanids had to meet to fall under the Odatria subgenus, but it only covers 'Dwarfs'. There are 3 or 4 subgenus that various monitors are classed under. Again, I know nothing more about it than that.
That's why I'm a keeper and not a bookworm