Labelled as Doryichthys deokhatoides, which might be correct (they might even have looked it up in the book on Asian pipefishes that I donated to Chester Zoo library). There were several young pipefishes on display in the tank, with a range of sizes, so I suspect that the zoo may have received a batch of wild-caught specimens, including a couple of gravid males. This individual was about 2.5 cm long and resembled a piece of button thread to the naked eye.
