The Pelican eel
Gulper
eel, Eurpharynx pelecanoides, or the pelican eel, also called the
umbrella mouth gulper. I think these pictures, especially of the gills,
are unique. This one is from a cod-end trawl off California at a depth
of 600 metres but apparently found much deeper too. These fish do not
survive long after being taken from so deep in a big net, the
temperature at the surface being much higher than where they live. The
recently dead specimen was filmed in a kreisel aquarium that had a
regular water flow and its skin texture and details are probably
identical to a living fish. It is about half a metre long but can swell
up with water to 11 times its volume and perhaps take quite large prey
in its expandable jaws. However, it has been found with small
crustaceans and plankton in its gut so perhaps filters the water like
some species of whales, sieving out the plankton. In this case it would
need to expel large amounts of water and you can see that it has some
strange gill slits situated about a third of the way down the body,
after the mouth, which might help in getting rid of huge mouthfuls of
water. The mouth itself is super matt black, suggesting it holds it open
for animals to blunder into in the dark.
There was a bioluminescent
organ on the tail but this is not seen here. Not a true eel - just looks
like one the internal anatomy is very different.
