Scientists described a new kind of small fish from deep waters off southern Australia. They named it the helmethead sea muppet because its head looks like it has a helmet. It is no longer than a thumb. It and two related kinds look like seahorses, but belong to a separate group.
Scientists have only seven of these fish, collected over about 65 years. Nets and other equipment caught them by accident, about 50 to 125 meters below the surface. The only helmethead came up in 2006. A museum put it in the wrong collection and did not recognize it for years.
Scientists could not cut open these rare fish, so they used detailed X-ray pictures to study their bones. Their bones differ from seahorse bones. One fish also provided DNA, the information inside living things that passes from parents to young. This showed that the fish belong outside the seahorse group.
The seahorse body shape developed separately in these related groups of fish. No one has ever seen a sea muppet alive, and no one has collected one in almost 20 years. Scientists now call them lost species, but this does not mean they have all died. The name marks them as important fish to search for.
