Sternarchogiton labiatus is a species of weakly electric knifefish in the family Apteronotidae. Its species name labiatus comes from the Latin labium, meaning "lip", referring to a distinctive three-lobed structure on its lower lips. S. labiatus is only known from the Rio Tefé, at a depth of 6–14 m, and from the lower Rio Negro, in the Amazon River basin. They have been captured from both whitewater and blackwater habitats.