Jon Lovitz, 58, and Jessica Lowndes, 27, spark relationship rumors with romantic new pics

Jessica Lowndes has been Instagramming all weekend about her new mystery man -- but is it Jon Lovitz?

The 58-year-old comedian tweeted out a photo of himself and the 27-year-old 90210 star riding in a Bentley convertible on Sunday. "Easter with my bunny, @jessicalowndes!!! ♥️♥️♥️," he captioned the pic. Lowndes also shared a selfie in the same car, writing: "His... ❤️.

See photos of the 27-year-old actress:

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In January, Lowndes and Lovitz were spotted in Honolulu taking photos of one another after they both guest starred in Hawaii Five-O together. "Who needs a selfie stick when your co-star is Jon Lovitz?" she Instagrammed at the time. "Throwback to one of the funniest and most random paparazzi moments 😂😂😂 #comedy #hawaii50 #tbt."

Lovitz shared this most recent photo just a few days after Lowndes posted a pic of a man with his hands between her legs. "There's a new man in my life," she wrote. "His hands are wise and tell a thousand stories... #smitten #hatersgonnahate."

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Further alluding that she was dating an older man (Lovitz is 33 years her senior), she quoted the Thai proverb, "Old cows love to eat young grass."

She added, "And I love me some old cows... 😘"

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She went on to post a pic from an ice cream date with the message: "You say sugar daddy but I say ice cream daddy! Lol 🍨🍦😍 #SweptoffMyFeet #ExtraSprinklesPleaseDaddy."

Lowndes also Instagrammed a video of herself in bed that she says was shot by her new guy. "When bae films you waking up in the morning... 😂❤️😍 #TooOldToUseHashtags #MrBig," she wrote.

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Whoever the actress is dating, it appears to be serious. "No, I haven't been hacked. I'm just really excited to be able to finally share this secret with you guys," Lowndes said in a video clip on Friday before sharing a close-up image of a huge diamond ring.

ET has reached out to both Lowndes and Lovitz for comment on the pics.

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