Scarlett Johansson Flaunts Slim Figure in Tight Orange Dress

 Alberto E. Rodriguez/WireImage

Skinny minny!

Scarlett Johansson showed off her super-slim bod in an orange Roland Mouret dress at Disney's D23 Expo in Anaheim, Calif. on Saturday. She accessorized with nude pumps, coral lipstick and styled her fiery hair in loose waves.

The actress, who split from Sean Penn earlier this summer, was promoting her new flick, The Avengers.

Back in April, a photo of the couple jogging in Malibu fueled speculation that ScarJo was pregnant. But her "baby bump" turned out to be the result of an unflattering shirt and camera angle.

"She's been training for The Avengers for over four months and is in the best shape of her life," her rep said.

An insider told Us Weekly, that the 50-year-old actor broke up with the stunning redhead, 26, after five months because he has not wanted anything "serious" since his 2010 divorce from Robin Wright, adding, "Scarlett pursued him."

The single star recently declined an invite to the Marine Corps Ball on Nov. 10 sue to "prior commitments," but she sent Sgt. Dustin L. Williams her regrets and a case of champagne!

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