Marianina khaleesi is a species of sea slugs, a dendronotid nudibranch, a marine gastropod mollusc in the family Tritoniidae.

[2] The specific name khaleesi is named after the title "Khaleesi" used by the fictional character Daenerys Targaryen in the fantasy novel series A Song of Ice and Fire.

The discoverers chose the name because the silver-colored band on the back of the slug reminded them of the pale blond hair of the character as played by Emilia Clarke in the television adaptation Game of Thrones.

[3] Marianina khaleesi was discovered off north-east Brazil in the South Atlantic Ocean and first described in 2013.

It is the only known Tritoniid with a unicuspid rachidian tooth in adult form.