FOX's staple animated comedy series The Simpsons has broken yet another record, taking the title of most episodes produced for a prime time scripted TV show from the classic Western drama series Gunsmoke. The cartoon celebrated with an opening parody in which Maggie has a showdown with Gunsmoke's hero Marshal Matt Dillon (who was played by the late James Arness in the TV series). Maggie gets the draw on Dillon, and The Simpsons takes the record.

This is merely the latest record for a series that has already taken many titles thanks to its longevity. The Simpsons is the longest-running animated series of all time (it's been on the air for almost thirty years, having debuted in December 1989), the longest-running American sitcom of all time, has featured more guest stars than any other TV series, and has won the most Emmy Awards for an animated TV show.

Sunday's episode of The Simpsons - season 29, episode 18, "Forgive and Regret" - was the 636th episode of the series, overtaking Gunsmoke's 635 episode count. "Forgive and Regret" featured the voice of Glenn Close as Homer's mother, Mona Simpson, and sees Abe Simpson - believing that he's on his deathbed - confess about something terrible that he did after Mona left the family due to being a wanted criminal. This leads Homer on a search for a lunchbox full of his mother's old recipes and affectionate notes to her son.

The Simpsons - Forgive and Regret

Glenn Close debuted as Mona Simpson in the season 7 episode "Mother Simpson," which first aired in November 1995 and told the story of how, as a hippie activist, she had to go on the run after destroying a lab where Mr. Burns was developing germ warfare. Close has since returned for a handful of episodes over the years, with Tress MacNeille also voicing the character in several episodes.

Though this is certainly an impressive record to break, overall The Simpsons has been suffering from a long, slow ratings decline over the past decade and a half, with many fans dropping off due to what they feel was a drop in quality. The show also recently faced criticism for its racial stereotyping in a documentary called The Problem With Apu, and responded to the controversy in a particular tone-deaf way. Still, The Simpsons continues to pull in around 4 million viewers every week, so it's unlikely to be canceled any time soon. There are still more records to break, after all.

More: The Simpsons Parodies Marvel Post-Credits Scenes

The Simpsons airs Sundays at 8/7c on FOX.