Why in Database: Note about the nameless turtles that appeared in the comics of the series Adventure Comics
Adventure Comics #135: An eight-page comic about Turtletown, a city where fast-moving is prohibited by law. (Which for the comic book hero, Johhny Quick, a Flash-like character that moves very fast, is problematic.) In a few frames you can see turtles, e.g. at the judge explaining the rules of the city.
Adventure Comics #377: In the comic, the metal-eating beasts of Rojun appear in a few frames. He, apart from an extra pair of legs, looks very turtle.