Mecistocephalus zygethus is a species of centipede in the Mecistocephalidae family.

It was described in 1939 by American myriapodologist Ralph Vary Chamberlin.

[1][2] This species is brown with yellow legs, can reach 35 mm in length, and has 51 pairs of legs.

[1] The species occurs in New Guinea.

The type locality is Doormanpad, Western New Guinea.