Sunday, February 27
A while ago I found a picture of a very unusual fish on a Japanese website, which I posted with a query in the vain hope some browsing ichthyologist might come across it and identify it for me. Fat chance. This is it, somewhat overcolorized but this is the picture as it appears on the website (if the colour is auto-adjusted the fish appears to be a light grey-green):
Thanks to the wonderfully informative and eponymously-named
Australian Museum Fishes Website, I thought for a while it might be a paddlefish. Here's one:
The trouble is it's not the right colour, and it has scales. Paddlefishes are primitive; unlike most modern fishes, they have skins with reduced scales, almost wholly cartilaginous skeletons, and upturned tail fins. They are a uniform leaden gray in color. However, there are plenty of different subspecies, including the Chinese paddlefish. Here's one of those:
It's the one at the bottom left, psephurus gladius.
Paddlefish are amazingly interesting. They are an ancient freshwater fish with a cartilagenous skeleton, that have similar morphology to sharks but are more related to the sturgeon. Paddlefish are one of the oldest fishes, with fossil records dating their first appearance at 300 to 400 million years ago (about 50 million years before the first dinosaurs. Paddlefish roe, like sturgeon roe or caviar is considered a great delicacy. The Chinese paddlefish is now very rare, found only in the Yangtze River and is called in China 'the panda of the river'.
"The American paddlefish (Polyodon spathula) and the
Chinese paddlefish (Psephurus gladius) are the only
living members of the family Polyodontidae. American
paddlefish are native to the United States where they
inhabit the Mississippi River and large rivers and
associated oxbows connected to the Mississippi River.
The paddlefish faintly resembles a shark based on its tail
structure, skin color, and lack of bones, but is more
closely related to sturgeons than sharks. Other features
of the paddlefish include a paddle-like snout and a gill
cover that extends greatly toward the rear of the fish.
The paddle was first believed to serve as a tool to disturb
the bottom substrate or aquatic vegetation and allow the
fish to capture organisms as they were dislodged.
However, it was later discovered that the paddle was
used as a sensory organ, enabling the fish to seek out
zooplankton, tiny crustaceans found in the water column
that are a preferred food source especially when they are
young. As the fish swims through concentrations of
zooplankton with their open mouth, zooplankton are
funneled along the gill arches of the fish where the gill
rakers filter out the plankton and move them toward the
So I'm actually no further forward on identifying that little fish, but I now have an abiding interest in paddlefish, so, swings and roundabouts. The request to any visiting icthyologist still stands.
This is what the internet is for.
UPDATE: I was watching a report about China's economic boom on BBC2's 'NewsNight' a couple of days ago (it's China week on the BBC) and the presenter was interviewing restaurant patrons at a 1000-seater seafood restaurant in Shanghai. What should he be standing in front of but the tanks from which live fish are taken to cook, which was full of, you guessed it, paddlefish.
So much for their protected status.
11/28/2004 - 12/05/2004