Rattails, or macrourids, are common throughout the world’s ocean. They are characterized by a distinctive large head and whip-like tail that tapers to a point. Big blue eyes give the rattail an edge at finding food in deep dark waters. Their keen eyesight reveals prey, like fishes and squid, darting just above the seafloor.
There are over 1,000 species of rattails found worldwide, although MBARI has recorded less than 20 species during our numerous expeditions. Macrourid species are difficult to distinguish on video, so researchers often use species complexes to describe similarly-looking species.