Scientists have described a new fish from deep reefs off southern Australia: the helmethead sea muppet. No longer than a thumb, it has a horse-shaped head, a gripping tail and, in males, a closed pouch for carrying young. Despite these similarities, it and two related species are not true seahorses.
The researchers used detailed X-ray scans to examine the fish without damaging the rare specimens. Unlike seahorses, they lack both a rigid cage of joined bony plates around the belly and a bony crown on the head. DNA from the new species confirmed that the three belong to a separate group. Their similar shape developed independently of true seahorses.
Only seven preserved specimens represent the group. All were caught accidentally by nets or equipment working on the seabed, at depths of about 50 to 125 metres. The new species was collected near the Gambier Islands in 2006, but was mistakenly stored in a museum collection for animals without backbones.
No specimen has been collected for nearly two decades, and nobody has ever seen these fish alive. They therefore qualify as ‘lost species’, but this label does not mean they are extinct. Instead, it identifies them as a priority for planned searches, rather than relying on another accidental catch.
