Panettiere took the stage for her appearance wearing a large brown and black boa -- constrictor, that is.
Hayden brought the snake to mess with Michael Strahan, who is deathly afraid of snakes. On her last appearance on the show she brought a fake rubber snake and tossed it at the host, and he vowed revenge. But Hayden one-upped her last trip to the show by bringing the real deal this time.
But while discussing Strahan's reptilian fears, co-host Kelly Ripa made a quick observation.
"I'm sort of distracted, not just by the snake, but there's a very large diamond ring on your finger," she said. "I'm not sure if you want to announce anything... Does that signify anything, is that a promise of something?"
Panettiere, 24, said that the ring "speaks for itself", but she grinned while confirming the news; saying, "I am!" when asked directly if she and Klitschko, 37, had gotten engaged.
The couple began dating in 2009 and split in 2011 because of their long-distance relationship, but they rekindled their romance earlier this year.