This Dalí-painting escapee lives up to 5.4 km* (3 miles) under the ocean in the abyssal zone, where it’s pitch black, freezing, with little to no oxygen or current, and there are up to 600 atmospheres pressing down on your head.
Just 440 atmospheres can crush a styrofoam cup into a thimble, so it sounds like a fun place to live. On the other hand, it’s calm, it’s quiet, and food generally finds you, usually in the form of tiny scraps from the surface or plankton. In order to reach said food and oxygen from the barren ocean floor, you need to prop yourself up a bit, and that’s where its other moniker “tripod fish” comes in.
The abyssal spiderfish’s lower fins are usually flexible, but to hold itself up it stiffens them, presumably by pumping them full of fluid. (Fnar fnar.) It wouldn’t actually get that joke though. Not because it’s hermaphroditic and doesn’t mate in the same way, but because it doesn’t speak English.
But back to talking about fish sex. Hermaphrodites are rare among vertebrates, and the abyssal spiderfish’s type even more so – it’s a “synchronous” or “simultaneous” hermaphrodite, so it has both male and female sex organs active at the same time. This means it can release eggs for its partner’s sperm, and then switch. Only 40 out of 25,000 fish species can do this, and it also makes self-fertilisation possible. It’s certainly not preferable, because a clone of any kind almost always turns out evil, but it avoids embarrassment if you can’t find a date in an area that’s 60% of the globe and 83% of the ocean.
Regardless of conquest, tripod fish tend to lay their eggs in the water column, with the larvae floating down from the prey-rich surface as they mature. We don’t know much else about their love lives though, because abyssal spiderfish tend to reproduce very slowly, in fact it would take about 14 years for their population to double. This makes it quite hard to study, even without the lethal pressures and depleted oxygen.
Living in such a welcoming environment obviously took a toll on its appearance, because it has tiny eyes and a disappointing lack of fabulous colours. But what’s the point if no one can see you? For hunting, mating and everything else it relies instead on its sensitive fins, some of which are motion sensors, or act like “hands” by wafting tiny crustaceans into its gaping maw. Oh, and it survives crush depth by having the same amount of pressure in its body. So bringing it up to the surface might literally blow its mind.
Latin: Bathypterois longipes
What? Wispy-looking deep-sea fish
Where? Worldwide except Antarctica, 2.6-5.4 km / 1.6-3 miles (!) under the sea in the abyssal zone
How big? Up to 25 cm / 9.8 “ long
Endangered? Nope, plenty of them, even though it takes more than 14 years to double a population
Probable motto: I care not for your surface nonsense of warmth, sunshine and weather.
They sound interesting. Do they need my help at all?
Not really, they’re one of the few that don’t need saving! Although helping their oceanic home wouldn’t hurt, and the abyssal zone receives most of its oxygen from the polar regions, which are sadly under threat.
Just to prove I’m not fibbing
Anderson, Maria. 2017. “Simultaneous hermaphrodites: Understanding Speciation in fish called “hamlets”. Smithsonian Insider.
Aquarium of the Pacific. No date. “Tripod fish near seafloor“.
“Bathypterois longipes“. No date. IUCN Red List of Threatened Species.
“Bathypterois longipes Günther, 1878″. No date. Fishbase.se.
“Bathypterois longipes Günther, 1878: WORMS taxon details“. No date. World Register of Marine Species.
Crew, Bec. 2014. “Tripod fish: a deep-sea fish able to ‘stand’“. Australian Geographic.
The Editors of Encyclopaedia Britannica. “Abyssal zone“. No date. Britannica.com.
Hureau, J.C. No date. “Abyssal spiderfish (Bathypterois longipes)”. Marine Species Identification Portal.
Kunzig, Robert. 2001. “The physics of…deep-sea animals“. Discover Magazine.
McGrouther, Mark. 2014. “Spiderfishes, Bathypterois spp“. Australian Museum.
Featured image credit: CSIRO Australian National Fish Collection.
*previously 2.6 km for some reason. Apologies! At least the miles were correct.