Comic book artist and cartoon storyboarder Jim Janes -- known for his work on such comics as Legion of Super-Heroes and shows as Teenage Mutant Ninja Turtles -- has passed away.

Janes' passing was confirmed on Twitter by former collaborator Paul Kupperberg. "I just learned of the death of artist Jim Janes, my long ago collaborator on the Secrets of the Legion of Super-Heroes miniseries," Kupperberg wrote. "Jim was a complete pro who didn't blink at these overstuffed scripts. 'It's the Legion,' he said. 'Bring them on!'"

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In addition to working on the three-part Secrets of the Legion of Super-Heroes series alongside writers Kupperberg and E. Nelson Bridwell in 1981, Janes also penciled no fewer than 15 issues of DC Comics' main Legion of Super-Heroes title from May of 1980 to December of '81. Some of his other DC credits include House of Mystery and Superman Family. He also did some work for Marvel Comics, penciling Marvel Comics Super Special #17 and Marvel Team-Up #95.

In the world of animation, Janes worked as a storyboard artist on numerous different shows, including RoboCob: Alpha Commando, Extreme Ghostbusters, Exosquad, the animated adaptation of The Karate Kid and 1987's Teenage Mutant Ninja Turtles. He also worked on numerous cartoons based on DC and Marvel properties, including Swamp Thing, Batman: The Animated Series, The Incredible Hulk, Spider-Man: The Animated Series and X-Men: The Animated Series.

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