Snailfish

Image: NOAA Okeanos Explorer Program, INDEX-SATAL 2010

More like Tadpolefish if you ask me. Who would've guessed that some of the deepest living fish in the world would look like a tadpole?

Snailfish are some 360 species in the family Liparidae, all reaching somewhere between 5 and 75 cm (2 to 30 in) in length.

Image: National Museums Northern Ireland

They are most closely related to the Lumpsuckers, and like them their pelvic fins are modified into an adhesive disk on their underside. It allows them to stick to rocks and such when they've had enough of swimming. Like how most people adhere to the sofa when they come home from work. Or to the office chair when they're at work. And the car seat on the way to work. And back. Oh, jeez... what have we become?

A lot of Snailfish really look like they'd need a good rest after any physical exertion. Probably before it, too. They're not fat exactly, but they look so... unhealthy!

They have no scales, just thin, gelatinous skin which is sometimes pink enough to make the whole fish look like a fillet of salmon. The head is large, the eyes small and the body deep from top to bottom but rather thin from side to side.

As you may suspect, they do not eat their greens. Snailfish hang out at the bottom of the sea and eat various invertebrates like crustaceans and worms. They should eat more seaweed, I hear it has antioxidants.

When they can muster the strength to swim, they do it primarily with their large pectoral fins. They also wriggle their body to help out, aided by their dorsal and anal fins merging with a tiny tail fin. You wouldn't think it to look at them, but Snailfish actually have really small tails. It's just that their entire body looks like one great, big tail directly attached to a large head.

Image: neptunecanada

I must say, it's not looking too good for our fleshy, pallid friends. I'm trying to be optimistic, but they look like they were invented by doctors as a warning of what happens if you don't heed their advice.

Where on earth can such a creature find a place in society to truly thrive? Where does the phantom go when all the backstage staff at the opera house go on strike and refuse to work until he leaves?

The deep sea, of course! Where the freaks dwell and you eat first, ask questions later. Like "maybe I shouldn't have eaten all the cookies."

As it turns out, Snailfish do extremely well in cold waters and not bad just about everywhere else. They can be found from the intertidal zone to the deepest of the deeps. In fact, the very deepest fish ever to be recorded alive was a Snailfish. Actually it was a whole group of them, their fins all a-flutter at a depth of 7,700 m (25,250 ft).

It's amazing to see them so active that far down, in all that darkness and cold. And how inspiring! Even the most corpse-like of us can find a place of lively, community spirit, even if it's in a place where normal people are immediately crushed to death.

Their disdain for the healthy complexion even allows them a great asset in the oblivion of the deep sea. Most would shrink from the idea of having horribly pockmarked skin on their face, but the Snailfish is totally fine with it. They'll just add it to their list of cool and funky defects.

In this case it's well worth it, because those pockmarks are actually pores which increase the sensitivity of their lateral line, which is extremely useful when you can't see much. Lots of fish and amphibians have a lateral line - it's a line of tiny hairs running all the way down the body that can sense the propagation of energy in water. It's similar to how we have hairs in our own ears which sense the propagation of energy in air. We call it "sound". The Snailfish probably calls it "food", "predator" and "uninteresting".

Image: NOAA Okeanos Explorer Program, INDEX-SATAL 2010
Dancing like a deep sea pixie!

Oh, and "mate". Snailfish only lay a few hundred eggs, compared to the "as many as theoretically possible" approach of most fish. Some Snailfish have even been seen mouth brooding, where a parent carries the eggs around in their mouth. I'm sure such news won't bring about the fall of cichlid as the aquarist's favourite mouth brooder, but it's impressive for such a sickly looking fish.

I'm starting to wonder if they have a precise constellation of illnesses that have balanced themselves out to render the Snailfish indestructible.