Many may have passed it off as an off-coloured strand of marine grass, however this rare fish did not go unnoticed by marine science masters student Ryan Weeks.

Mr Weeks’s quick reach for a camera proved to be much more than an opportune photo-grab - it was the first confirmed record of a Hypselognathus rostratus in the Tamar River.

The convincingly camouflaged creature, the knife snout pipefish in laymen’s terms, is a member of the syngnathid family which also includes seahorses and seadragons.

Mr Weeks said the chance viewing occurred while gathering seagrass samples for his thesis at the Institute of Marine and Antarctic Studies Launceston.

‘‘I knew it was a pipefish, but other than that I didn’t know what species it was and it took us a fair while to actually work out,’’ he said.

‘‘I had a few discussions with the academics there who suggested it might have been this species, but we couldn’t confirm it until I talked to a specialist in Newcastle.’’

He said the knife snout pipefish is usually a resident of Victorian waters, and that the discovery could help raise awareness about the estuary’s delicate and charismatic ecology.

‘‘It would be interesting to go out and see if its distribution goes further, or if it was just a once-off, it’s probably fairly likely we’ll see them more commonly down here with warmer temperatures,’’ Mr Weeks said.

‘‘I suppose it just shows how little we know about our environment, or how it may be changing.’’

He said  the pipefish discovered in the Tamar was definitely an adult specimen.