WHAT'S DA BUZZ ON LEO DI-MOSQUITO?

BUGGED! LEONARDO DICAPRIO slammed the shutters shut on promoting his flick “Shutter Island” on DAVID LETTERMAN’s TV show, opting instead to appear on rival JAY LENO’s new mid-evening extravaganza – and here’s da buzzzzz: Leo hates Dave for making the stinging remark that he “looks like a mosquito” while intro-ing a February “Late Show” intvu with Leo’s then-galpal, supermodel BAR REFAELI.

Leo’s good pals with Jay and wants to help him launch his new show – but when “Shutter” producers suggested booking Letterman as well, Leo snarled: BUZZ OFF!