Hot yacht stuff!

Late last month, Jennifer Aniston and Justin Theroux capped off their European vacation (with stops in Paris and Rome) for a sun-filled, five-day trip to the sunny, celeb-friendly Italian island of Capri.

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And, as exclusive Us Weekly photos reveal, the 43-year-old Wanderlust star and her beau, 40, caught plenty of rays June 19 aboard a rented luxury yacht. Alongside a shirtless (and seriously buff!) Theroux, Aniston flaunted her world-famous, yoga-toned body in a skimpy two-piece bikini -- with a red top and black bottom.

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An island source tells Us the couple of one year "sunbathed but didn't swim" aboard the Liberty of Lymington, which rents for $17,555 a week; the 60-foot vessel stopped for lunch in the Gulf of Naples during their June 19 sail.

Once on dry land, they kicked back at a $3,750-a-night suite at the JK Place hotel in Marina Grande, where the couple of one year were frequently seen dining al fresco.

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As for the most recent rumors of a planned wedding between the pair? "If there are plans for a wedding," one confidante says, "it would be some type of elopement."

This article originally appeared on Jennifer Aniston Flaunts Hot Bikini Body in Capri With Justin Theroux!