418 Dive Log Australasia JUNE 2026.pdf

Snuffleupagus from the Great Barrier Reef photo credit David Harasti.

male–female pair, and Al’s photograph of the green-coloured individual (the only one anyone has ever seen) both made it into our paper. Without their eyes underwater, we’d never have written it. Two dives that ended a 20-year hunt In 2020, the Smiths got in touch with fresh photographs from the GBR. We flew to Cairns and went straight to Saxon Reef. Nothing on the first dive. The second dive that day was at a nearby site, just along the reef. Fifteen metres down, tucked into a coral nook thick with red filamentous algae, there they were: not one but two of the shaggy little fish. A male and a female. Enough to describe a species. There were certain regulator noises that we will spare you. There was an underwater high-five. There was also, definitely, a hug. Twenty years of fieldwork had just resolved With the 2020 fish in hand, we brought them to the Australian Museum, the same institution whose 1993 expedition had collected the original specimens. Credit here is due to Helen Larson, the ichthyologist on that 1993 expedition, who recognised at the time that the two specimens didn’t fit any described ghost pipefish species and catalogued them simply as Solenostomus sp. Without her early recognition that something was off, the specimens would have been filed under a known name and lost to us for good. With the historic and the new material finally together, we could do the side by-side morphological comparison the case had been waiting for. This is also where Kerryn Parkinson at the Australian Museum joined the project. Kerryn carried out the micro-CT imaging that became central to the description. A micro-CT scanner is essentially a medical CT scanner built for very small specimens; it produces detailed 3D reconstructions of every bone without having to dissect the fish. Kerryn’s scans itself into about a square metre of red algae. The Australian Museum picks up the baton

let us count vertebrae, examine the small bones of the fins and skull, and characterise features that would have been inaccessible by any conventional means on a specimen shorter than your little finger. She also identified something none of us had expected: tucked away in the gut of the female specimen, the scan revealed the half-digested skeletal remains of small fish. Several things pointed toward a new species from the beginning, but the most striking was the sheer density of the filaments. S. paegnius has filaments only in a few discrete tufts under the snout. This fish was shaggy from head to tail. The micro-CT scans, the morphology and the genetics all backed this up. Solenostomus snuffleupagus has 36 vertebrae. Every other ghost pipefish has 32 to 34. Its body is shorter and stockier through the chest. It has a couple of distinctive anchor-shaped little bones in its fins that other ghost pipefishes don’t. And its DNA differs from its closest cousin by 22 per cent, a big gap in fish terms, suggesting the two lineages went their separate ways around 18 million years ago. The hairy ghost pipefish has been its own species since long before there were coral reefs in their current form to swim around in. Two of our findings are worth dwelling on. Female ghost pipefishes are nearly twice the size of males, and unlike their seahorse cousins it’s the female that broods the eggs, carrying them in a pouch formed by her belly fins, which are joined together to make a kind of basket. And ghost pipefishes were thought to feed exclusively on tiny shrimps and plankton; Kerryn’s gut-content imaging shows that at least one of them, at least sometimes, eats other fish. For such a cute little thing, it’s actually a predator. Why a name matters You can’t protect what doesn’t have a name. Until last month, the hairy ghost pipefish didn’t officially exist. It couldn’t be listed under any state or Commonwealth threatened species legislation. It couldn’t be flagged in marine park management plans. It couldn’t even be properly counted. Naming it

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DiveLogAustralasia #418 June ‘26

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