Rubeosaurus is derived from the Latin "rubeus" (thornbush or bramble, aka blackberry bush) and the Greek "sauros" (lizard), named for the array of spikes adorning its frill. The species epithet, ovatus, means "egg-shaped" in Latin. The name was coined by American paleontologist and Herman Munster look-a-like Charles Whitney Gilmore in 1930 for the shape of its frill.
This puzzle is great for ages 4+ years.