Tiny pipefish in Solomon Islands

I was floating next to a clump of tunicates, sponges, and other miscelleneous non-mobile critters when I noticed one of the small tubes moving, which turned out to be a tiny pipefish. When not illuminated by strobe light, the perceived color looked exactly like one of the red/brown tube sponge thingies. But it's more orange/red when flashed with a strobe.

No fan tail, and maybe 1.5 inches long. Any idea what it might be?

I vote Pygmy Pipefish Micrognathus pygmaeus

No idea. But the specimen appears to be an adult male judging by the apparent brood pouch down the side.

It's not Micrognathus pygmaeus because that species has a tail fan. The closest I could find is the dwarf pipefish Acentronura tentaculata (in the addendum of Fishes of the Great Barrier Reef and Coral Sea by Randall, Allen and Steene). The authors say "no caudal fin; tail prehensile like a seahorse,. Color variable, often mottled dark greenish brown". But this guy is apparently an adult and way shorter than the 6.5 cm quoted by Randall et al.

Probably a new species.

Good find.

Cheers (and beers),

Paddy

Taking a second look at the pics I noticed that at least some of the tubes are soft corals rather than sponges. The individuals in the crop clearly have 8 tentacles around a central mouth.

A species of pygmy pipehorse? No tail fan may point in that direction

Anymore possibilities on this guy? (round two if ID!)

Eric - Why don't you send the images to Rudie Kuiter who wrote the book on pipefish ("Seahorses, Pipefishes and Their Relatives - A Comprehensive Guide to Syngnathiformes")

I sent Rudie an email to have a look at this thread and/or the photographs.

Rudie has replied already. He believes it is Cosmocampus banneri or a closely related undescribed species. He says it should have 15 trunk rings and the dorsal fin should start just ahead of where the pouch begins which might be visible in the original photographs. That species actually comes from Japan but Rudie thinks the species and species complexes need some detailed sorting out.

Good on ya, Andrew!

Thank you! i'll take a closer look at the images and count rings.