Meet the Great Southern Reef’s ‘Sea Muppets’
A thumb-sized fish collected from about 50 metres below the surface at the entrance to South Australia’s Spencer Gulf has been formally described as a new species.
The specimen came from waters between Wedge Island and the Neptune Islands at the mouth of Spencer Gulf, between the southern ends of Eyre and Yorke peninsulas. It was collected incidentally by a dredge surveying marine invertebrates during a South Australian Museum-affiliated expedition.
Images: Graham Short
The fish, now named Australyichthys aegis, belongs to Syngnathidae, the family that includes seahorses, pipefishes, pipehorses and seadragons. Researchers created the new genus Australyichthys to include this species and two fishes previously classified as seahorses.
Researchers gave members of this newly recognised genus the common name “sea muppets”. Their prominent domed heads and fleshy lobes reminded the researchers of characters from The Muppet Show.
With its downward-angled head, grasping tail and enclosed male brood pouch, Australyichthys looks remarkably like a seahorse. Micro-CT scans and genetic analysis showed that it belongs to an evolutionary lineage separate from true seahorses, meaning these seahorse-like features evolved independently.
All known specimens were collected from mesophotic habitats between 50 and 124 metres deep, stretching from Eden to Esperance. None has ever been observed alive in its habitat, and researchers say no targeted, non-extractive surveys have been conducted for the genus.
Fig 11. from Short et al 2026. Known collection sites for the three Australyichthys species, all found as trawl bycatch at depths of 50 to 124 metres across southern Australia.Large areas of seafloor across the Great Southern Reef’s mesophotic zone remain poorly surveyed. This museum find reminds us how much remains unknown. Perhaps it’s time to raise the curtain on these deeper reefs. There may be a whole cast of strange characters waiting in the wings.
All Images by Graham Short. 
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