Meet the Flapjack Octopus
Picture a soft, flattened body drifting through total darkness, far below where sunlight ever reaches. That’s the flapjack octopus, and it doesn’t look like it belongs on this planet. It’s small, it’s gelatinous, and it has an oddly endearing shape that has earned it a small cult following among marine enthusiasts who stumble across footage of it online. But don’t let the charm fool you. A 2025 CSIRO report on the newly described Carnarvon Flapjack Octopus found that some members of the group reach only about 4 cm in diameter, making them among the smallest of the deep-sea octopuses.
This deep-sea species plays a real part in its ecosystem, and researchers still have plenty to learn about how it survives down there. Its habitat, its habits, and the pressure it lives under all shape a creature that’s stranger, and hardier, than its cute reputation suggests.
Why the Flapjack Octopus Stands Out
Start with the body. It’s soft, it’s gelatinous, and it belongs to the genus Opisthoteuthis, a group built to withstand crushing high-pressure depths that would flatten almost anything else. Then there’s the movement: a “parachuting” motion that lets the flapjack octopus glide rather than swim, saving precious energy in an environment where every calorie counts. Compare it to its cousin, the umbrella octopus, and the differences between the two cirrate groups become sharper and more interesting.
And the research keeps paying off. Every study into the flapjack octopus adds another piece to how scientists understand marine evolution and the wider dynamics of deep-sea ecosystems.
Classification and Family: Where Opisthoteuthis Fits
Here’s the thing about the flapjack octopus: it isn’t just a curiosity, it’s a genuine puzzle for marine biologists. This deep-sea octopus lives somewhere most of us will never see, and that alone makes it worth understanding. Flapjack octopuses are pelagic mollusks, meaning they drift through open water rather than clinging to the seabed, and that lifestyle alone sets them apart from the mollusk cousins you’d recognise more easily. Some of their most striking features come from what they don’t do. The specimens used to describe the Carnarvon Flapjack Octopus, for instance, were collected from depths of 1,044 to 1,510 m in and around Carnarvon Canyon and Gascoyne Marine Parks off Western Australia, according to CSIRO, underscoring just how far down this genus makes its home.
The octopus flapjack can’t change color, unlike many of its relatives, and its body flattens out rather than staying rounded. Look past the cartoonish look and you’ll find an animal built with real purpose.
Inside the Genus and Its Unusual Species
You’d expect a soft-bodied deep-sea animal to lean hard on camouflage, and the flapjack octopus does, just not the way you’d think. It can’t shift color like many of its octopus relatives, and that limitation doesn’t slow it down one bit. Instead, it blends into the ocean floor using a smooth, gelatinous surface that reflects ambient light the same way its surroundings do. Simple, effective, and it doesn’t need a single pigment cell to pull it off.
Then there’s the way it gets around. Flapjack octopuses are pelagic, so they’re not tied to the seabed. They float, and when they want to move, they use a “parachuting” motion, flattening their bodies and spreading their skirt-like webbing to drift. It’s not a party trick.
It’s a strategic way to cover distance in the vast ocean depths without burning energy the animal can’t easily replace. Startle one and it spreads its arms and webbing wide, creating a bigger silhouette that can put off a predator mid-approach.
Feeding follows the same patient logic. Flapjack octopuses are opportunistic feeders, taking small fish and plankton as they drift past rather than chasing anything down. Patience over speed, stealth over confrontation. It’s an evolutionary approach built for a place where food is scarce and every failed hunt costs more than it should. CSIRO notes that flapjack octopuses also have large eyes relative to their body size, an adaptation that improves prey detection in the dim deep sea, and that their diet includes worms and small crustaceans captured and consumed with their tentacles.
Flapjack Octopus versus Umbrella Octopus
The flapjack octopus sits inside the Opisthoteuthis genus, part of the Grimpoteuthidae family, and that family houses species built with distinct adaptations for deep-sea life. These animals get studied precisely because of how they’ve evolved to survive where sunlight is scarce and pressure is immense. Look closely at the classification of these octopuses and you start seeing the connections between species across the genus, connections that matter far beyond taxonomy. Understanding how one species adapted often explains how its neighbours did too.
What Sets Their Features and Habitats Apart
The Opisthoteuthis flapjack octopus and its close relatives in the genus make for a genuinely fascinating case study in adaptation. Take Opisthoteuthis carnarvonensis, one notable species in the genus: it displays characteristics shaped entirely by the harsh conditions it calls home, just like its relatives do. The Grimpoteuthidae family, home to the genus Opisthoteuthis, stands out for a soft, gelatinous body structure that lets its members survive at depths few other animals can tolerate. That single anatomical trait is what allows them to withstand the immense pressure of their usual habitat.
Naming and cataloguing these species matters more than it might seem. Every time researchers identify and describe an Opisthoteuthis species, they add to the catalogue of ocean biodiversity and to what we know about how marine life evolved. Take color, for instance. These octopuses have evolved to rely on it far less than their relatives do, and that alone keeps the genus a subject of real scientific interest.
Rather than flashing color to communicate or hide, they lean on their soft bodies to melt into the murky depths and stay off a predator’s radar. Study the genus long enough and a picture emerges: intriguing survival mechanisms, remarkable adaptability, and biology tuned for one of the planet’s toughest environments, from how they feed to how they move. Every fresh discovery about Opisthoteuthis expands not just what we know about these animals, but what their evolutionary strategies tell us about marine evolution and ecology more broadly.
How Scientists Are Uncovering the Flapjack Octopus
Set the flapjack octopus next to the umbrella octopus and the differences jump out fast. Both count as cirrate octopuses, but their paths diverged. The flapjack flattens its body into something close to a pancake shape and spends its life in pelagic, open-water environments. The umbrella octopus, on the other hand, carves out different niches within the marine ecosystem entirely.
Line up their habitats and their physiology side by side and you get a much clearer sense of just how varied deep-sea octopuses really are, and how differently two closely related species can end up living.
Pioneering Research in Marine Biology
Look closer at flapjack and umbrella octopuses and the adaptations each one leans on for survival become even more distinct. Flapjack octopuses, part of the wider cirrate octopus group, carry flattened, umbrella-like bodies that give them their signature pancake look. Pair that shape with gelatinous skin and you get camouflage that works directly against the ocean floor, boosting survival odds in the deep sea. They mostly stick to pelagic zones, floating and “parachuting” their way across huge stretches of ocean, feeding opportunistically on whatever plankton and small fish drift within reach of a sparse environment.
The umbrella octopus tells a different story. It can expand its webbed tentacles into a dramatic silhouette, a defence mechanism all its own, and rather than drifting endlessly like the flapjack, it often settles into more benthic zones with real structure: crevices, complex terrain, places that offer cover and feeding opportunities the open water doesn’t. Both species sit under the cirrate octopus banner, yet their strategies split hard. The flapjack’s pelagic lifestyle reflects an evolutionary bet on stealth and energy conservation.
The umbrella octopus bet on structural adaptation instead, carving out its own ecological niche in the benthic world. Set the two side by side and you get a genuinely richer sense of octopus biodiversity, and of just how differently environmental pressure can shape two relatives.
How the Flapjack Octopus Behaves in the Deep
Marine biologists keep circling back to the flapjack octopus because so much of its physiology, habitat and behavior still needs unpacking. Every study adds to a broader picture of how deep-sea ecosystems function and how creatures like this one evolved to handle conditions most animals never face. So what have researchers actually found chasing this creature through some of the ocean’s darkest corners?
Adaptations That Keep It Alive Down There
Submersible technology changed the game. Advanced submersibles let researchers reach regions of the ocean that were once completely inaccessible, and that access is what made direct observation of flapjack octopuses in their natural habitat possible in the first place. Watching the animal where it actually lives, rather than guessing from fragments, is what turned assumption into real insight about its behavior and ecological role.
That fieldwork matters for a wider reason too. Understanding how the flapjack octopus survives extreme pressure, near-freezing cold and total darkness tells researchers something about deep-sea life generally, not just about one species. Careful observation has confirmed what makes this animal tick: a gelatinous body and the ability to flatten itself, both doing real work in how it survives and interacts with its surroundings. Each new discovery builds toward a fuller model of deep-sea ecosystems and feeds fresh hypotheses about how marine life adapts at depth.
None of this stays purely academic, either. Documenting how vulnerable deep-sea species are amid shifting ocean conditions is exactly what drives conservation efforts forward. Marine biologists are working, through collaborative research, toward real protection measures for animals like the flapjack octopus, and that focus on conservation is what keeps this research from being just curiosity for curiosity’s sake.
So how does the animal actually put all this to use day to day? Its flattened, pancake-like shape helps it evade predators, and its locomotion is efficient enough to make it, in its own quiet way, a master of the ocean’s depths. Look at the body itself and the survival strategy becomes obvious. Flattening into that pancake shape isn’t cosmetic: it reduces the animal’s silhouette and makes it harder for predators to spot in the first place.
Add the gelatinous body and umbrella-like webbing and you get an animal that mirrors the light bouncing off the sandy ocean floor closely enough to nearly disappear.
Locomotion works the same way. That signature “parachuting” motion lets the flapjack octopus travel the ocean while spending barely any energy at all, using its buoyancy and webbing the way a parachute uses air. It’s a dual-purpose trick: the same motion that conserves energy also lets the animal puff up into a larger, more intimidating profile the instant it feels threatened. Down in nutrient-barren depths, that kind of efficiency isn’t a bonus.
It’s the difference between surviving the week and not.
Diet reinforces the pattern. As opportunistic feeders, flapjack octopuses take small fish and plankton as they drift past, relying on patience punctuated by sudden, decisive action rather than active pursuit. It’s a hunting style built for scarcity, and it shows just how tightly this species’ survival is bound to its adaptations and behavior. Every trait, from body shape to hunting style, points the same direction: an animal precisely tuned to one of the harshest environments on the planet.
Study the flapjack octopus long enough and you come away with a sharper sense of how deep-sea ecosystems actually hold together. It’s an animal that earns its appeal honestly, through genuine adaptation rather than novelty, and its story is a reminder of how much of the ocean’s biodiversity still deserves protecting. As research continues, understanding of the deep sea keeps expanding, one flapjack octopus at a time, and so does the case for taking its conservation seriously.
