A race of nearly identical aliens, the Marklar who use Marklar in place of every noun. Don't worry - it's all about context! They are a generous race and have gratefully allowed Earth to send it's starving Ethiopians to their planet, where they co-exist in harmony. They are also a resilient race, having survived Xenu's wrath - and a cultured one, participating in the annual Biggest Douche ceremony.
- "Greetings. Welcome to Marklar. I am Marklar, leader of the Marklar." (Starvin' Marvin in Space)
- Starvin' Marvin in Space (s03e11; debut)
- The Red Badge of Gayness (s03e14; cameo)
- The Biggest Douche in the Universe (s06e15; cameo)
- Cancelled (s07e04; mentioned)
- I'm a Little Bit Country (s07e01; cameo)
- Trapped in the Closet (s09e12; cameo)
- A History Channel Thanksgiving (s15e13; preview only)
- In the preview for "A History Channel Thanksgiving", the planet Marklar is visible on a map of the Milky Way Galaxy, along with Plymouth, Indi, Earth and Green Lantern World. In the final episode, however, it is removed.