Ariana Madix and Lisa Vanderpump Hit Up White House Correspondents' Dinner

Ariana Madix took her road show to D.C. Saturday night ... and she had to get a boatload of satisfaction when someone hurled a joke into the crowd ... comparing her ex to Tucker Carlson!!!

Ariana and boss woman Lisa Vanderpump were invited guests of DailyMail.com at the White House Correspondents' Dinner. M.C. Roy Wood Jr. dropped the comparison in the middle of his roast ... "The untouchable Tucker Carlson is out of a job… but to Tucker’s staff, I want you to know that I know what you’re feeling. I work at The Daily Show, so I too have been blindsided by the sudden departure of the host of a fake news program. Tucker got caught up. Got caught up like that dude from Vanderpump Rules."

Of course, Roy was referring to the Scandoval ... specifically Tom Sandoval.

Ariana's been on a world tour lately ... doing karaoke in Europe and getting tight with a dude at Coachella. She's movin' on ... so where's that reunion show!