December 25, 2025
2 min read
From the first sighting of a colossal squid in the wild to a seriously goofy octopus, 2025 delivered some astounding photos from the ocean’s depths
By Andrea Thompson edited by Jeanna Bryner
The mystery mollusk *Bathydevius cau…
December 25, 2025
2 min read
From the first sighting of a colossal squid in the wild to a seriously goofy octopus, 2025 delivered some astounding photos from the ocean’s depths
By Andrea Thompson edited by Jeanna Bryner
The mystery mollusk Bathydevius caudactylus observed at a depth of approximately 1,550 meters. It has a wide, paddlelike tail with several fingerlike projections called dactyls that may help with defense.
© 2021 MBARI
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A lot of weird-looking life-forms lurk in the deep sea, and this year we got some spectacularly close looks at several of them, including a goofy Doctor Who–esque octopus, alienlike Antarctic dwellers and the first-ever footage of a colossal squid in the wild. We’ve rounded up a few of our favorite ocean oddities below.
‘Mystery Mollusk’ Is a Mystery No More
For more than two decades, scientists at California’s Monterey Bay Aquarium Research Institute have occasionally spotted a little translucent creature in the ocean’s “midnight zone.” The gelatinous blob uses a hood surrounding its head to catch prey and has detachable tentacles; its hood and tail are decorated with glowing blue-green dots. This year, scientists finally figured out what it is—the “mystery mollusk” is actually a nudibranch, or sea slug. In fact, it’s from an entirely new family of nudibranchs and has been dubbed Bathydevius caudactylus.
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Baby Squid, Doo Doo Doo
People have known about colossal squids for 100 years, but these enigmatic ocean denizens—which can grow to 23 feet in length—had never been observed in their natural habitat. That changed this year when Schmidt Ocean Institute scientists captured the first video of one about 2,000 feet below the ocean’s surface in the remote South Atlantic Ocean. This particular squid wasn’t so colossal, though—it was a baby measuring only about one foot in length.
A large sponge, a cluster of anemones, and other life is seen nearly 230 meters deep at an area of the seabed that was very recently covered by the George VI Ice Shelf in Antarctica. Sponges can grow very slowly, sometimes less than two centimeters a year, so the size of this specimen suggests this community has been active for decades, perhaps even hundreds of years.
ROV SuBastian/Schmidt Ocean Institute
What’s under an Iceberg?
When an iceberg the size of Chicago broke away from an Antarctic ice shelf on January 13, Schmidt Ocean Institute scientists raced over in their *Falkor (too) *research vessel to glimpse what life-forms had been dwelling below. “There was a sense of going into a complete unknown,” said the expedition’s co-chief scientist Sasha Montelli of University College London. What they found was a vibrant and alienlike ecosystem of anemones, sea spiders, icefish and octopuses—including some new species—that had been living there for decades or even hundreds of years.
ROV SuBastian/Schmidt Ocean Institute
Deep-Sea Noir
On a mission to explore methane seeps off the coast of Chile, the Schmidt researchers also explored several submarine canyons where they snapped this dark, dramatic photo of an anglerfish. These canyons are carved by strong currents that funnel sediments, nutrients and organisms through the system. The flow acts like a moving buffet for creatures like this fish, which the deep-sea detectives are still trying to identify.
A siphonophore documented at 1,250 meters deep in the Mar del Plata Canyon.
ROV SuBastian/Schmidt Ocean Institute (CC BY-NC)
Hiding in Pink Sight
Off the coast of Argentina and two miles below the ocean’s surface, the Schmidt scientists viewed yet more marine wonders in a canyon twice as deep as the Grand Canyon. Here, two currents come together—one salty and from the tropics, the other cold and from Antarctica—supporting rich biodiversity. Many of the animals, like the beautiful siphonophore above, come in peachy-pink hues—that’s because red light doesn’t travel far in the dark ocean’s depths, providing the perfect camouflage.
A translucent telescope octopus floats in the deep sea.
ROV SuBastian/Schmidt Ocean Institute (CC BY-NC)
The Goofiest Octopus You’ll Ever See
One of our very favorite images from the year came from the same canyon. The team spotted this translucent telescope octopus floating upside down and—for the Doctor Who fans out there—giving serious Lady Cassandra vibes.
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