ROV SuBastian/Schmidt Ocean Institute
The expedition led by the Schmidt Ocean Institute observed a rare octopus species informally named the Casper octopus in the Southern Pacific for the first time. Discovered in 2016 and nicknamed Casper, the species has not been scientifically described or formally named, as no one has collected a specimen yet.
Schmidt Ocean Institute
During this expedition, the research vessel Falkor (too) discovered, mapped, and explored a new seamount. It covers an area of about 70 square kilometers. The summit depth is 994 meters and the base is at 4,103 meters giving it a prominence of 3,109 meters over the surrounding seafloor.
ROV SuBastian/Schmidt Ocean Institute
A rarely seen Bathyphysa conifera, commonly known as flying spaghetti monster, was filmed while exploring the seamount.
ROV SuBastian/Schmidt Ocean Institute
The ridge was home to deep sea corals such as this large bamboo coral holding benthic ctenophores (comb jellies), barnacles, a sea star, and brittle stars.
ROV SuBastian/Schmidt Ocean Institute
This scorpion fish (Helicolenus lengerichi) was documented by the expedition to characterize biodiversity along this underwater mountain range in the high seas off the coast of South America.
ROV SuBastian/Schmidt Ocean Institute
A sea urchin in the genus Argopatagus, thought to be one of around 20 new species discovered during the expedition.
ROV SuBastian/Schmidt Ocean Institute
The researchers collected the first live footage of Promachoteuthis squid during the expedition. Until now, the squid genus had only been characterized from dead samples found in nets.
ROV SuBastian/Schmidt Ocean Institute
A deep-sea starfish belonging to the genus Hymenaster. Experts are verifying whether it's a newly discovered species.
ROV SuBastian/Schmidt Ocean Institute
Bubblegum coral (Paragorgia) covered with Midas touch (Yellow Parazoanthidae), was documented on the seamount.
Misha Vallejo Prut/Schmidt Ocean Institute
Oceanographic research vessel Falkor (too) in the South Pacific, sailing above the Nazca Ridge, an underwater seamount chain off the coast of Chile.

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CNN  — 

Imagine four skyscrapers the height of Burj Khalifa, the world’s tallest building, stacked on top of one another.

That’s almost the height of an underwater mountain newly discovered and mapped by oceanographers led by the Schmidt Ocean Institute in California.

Located in the Pacific Ocean 900 miles (1,448 kilometers) off the coast of Chile, the seamount is 1.9 miles (3,109 meters) tall and part of an underwater mountain range that is home to sponge gardens, ancient corals and rare marine species — including a type of squid that was filmed for the first time.

A team led by the Schmidt Ocean Institute explored the region using the R/V Falkor (too) research vessel during a 28-day expedition that wrapped up this month. The researchers mapped the mountain using a sonar system under the ship’s hull.

“Sound waves go down and they bounce back off the surface, and we measure the time it takes to come back and get measured. From that we get a really good idea (of the seabed topography),” said Jyotika Virmani, the institute’s executive director.

“It’s important because at the moment only about 26% of the seafloor has been mapped to this kind of resolution. And the seafloor covers 71% of our planet’s surface.”

00:54 - Source: CNN
Rare species caught on camera in underwater mountain range

Oceanographers estimate that there are at least 100,000 seamounts higher than 1,000 meters (3,280 feet) around the world. They provide important habitats for a variety of species. The newly mapped underwater mountain is bigger than Mount Olympus in Greece, which is 2,917 meters (9,570 feet) high; smaller than Japan’s Mount Fuji, which stands 3,776 meters (12,388 feet) tall; and almost quadruple the 830-meter (2,723-foot) height of Burj Khalifa, the Dubai tower.

Spaghetti monsters, a ghostly octopus and a rare squid

Using an underwater robot, the team explored one of the mountain’s ridges, finding a region rich in marine biodiversity.

The researchers documented a ghostly white Casper octopus, marking the first time this deep-dwelling cephalopod has been seen in the southern Pacific. They also spotted two rare Bathyphysa siphonophores, sometimes known as flying spaghetti monsters for their stringlike appearance.

“The (Casper) octopus has never been captured, so it doesn’t actually have a scientific name yet,” Virmani said.

The team also recorded the first footage of a live Promachoteuthis squid, known only from a few collected specimens.

ROV SuBastian/Schmidt Ocean Institute
A rarely seen Bathyphysa conifera, commonly known as a flying spaghetti monster, was documented while the research team was surveying an unnamed and unexplored seamount along the Nazca Ridge off the coast of Chile.

The discoveries were highlights of the research vessel’s third expedition this year to the Nazca Ridge, which is in international waters. The region could be a contender for the world’s first high seas marine protected area under a new UN treaty adopted in 2023 that is being ratified by states, Virmani said.

“Across the three expeditions, we managed to map and explore 25 seamounts, which is quite a number to explore,” she said. “I think we’ve got some good data as a community that could be put forward to make the case that this is a really interesting region for protection.”

The two previous expeditions in January and February cataloged 150 previously unknown species. An additional 20 potential news species were collected during the most recent expedition.

Details of the newly discovered species will be shared with the Ocean Census, an ambitious international collaboration to record marine life hidden in the world’s oceans. It aims to identify 100,000 unknown species in the next 10 years, allowing scientists to better understand and protect the deep-sea ecosystem.

Editor’s Note: Call to Earth is a CNN editorial series committed to reporting on the environmental challenges facing our planet, together with the solutions. Rolex’s Perpetual Planet Initiative has partnered with CNN to drive awareness and education around key sustainability issues and to inspire positive action.