Australian scientists identify new deep‑reef fish Australyichthys aegis

Researchers have described a new species of deep‑reef fish, Australyichthys aegis, from southern Australia. The thumb‑sized fish closely resembles a seahorse, leading to its nickname “helmethead sea muppet.” It belongs to a small group that also includes the bullneck and paradoxical sea muppets, each placed on a distinct branch of the fish family tree.

The species was uncovered from museum collections after specimens, collected by trawl nets between 50 and 125 m depth over the past 65 years, were re‑examined using micro‑CT scanning. The single type specimen was caught in 2006 near the Gambier Islands at the mouth of Spencer Gulf and had been misfiled in the South Australian Museum’s invertebrate collection. Only seven specimens are known, held by the South Australian Museum, Australian Museum, Museums Victoria and CSIRO. The study, published in the Journal of Lost Species, highlights how overlooked museum material can reveal hidden biodiversity.