Corythoichthys amplexus, known commonly as the Brown-banded Pipefish, is a species of marine fish in the family Syngnathidae. The Brown-banded Pipefish is widespread throughout the tropical waters of the Indo-West Pacific region, from the eastern coast of Africa to the Samoa Islands. The Brown-banded Pipefish is a small size fish and can reach a maximum size of 10 cm length.