The Triceratops was a genus of Earth dinosaur which went extinct about 65 million years before the late 24th century.
Doctor Noonien Soong kept a model of a Triceratops skeleton in his laboratory on Terlina III. (TNG: "Brothers"; VOY: "Distant Origin")
Although not specifically stated on screen, Triceratops lived during the Cretaceous period in what would become the continent of North America.