Deep-dwelling ‘Emperor Dumbo’ octopus discovered
Anew species of Dumbo octopus, equipped with the telltale fins on its head, has been dredged from the deep. Nicknamed the Emperor Dumbo, the adorable creature was discovered in 2016. Alexander Ziegler of
Friedrich Wilhelms Universität in Bonn, Germany, was aboard the German survey ship RV Sonne as the resident biologist when a strange creature was caught in one of its nets near the Aleutian Islands.
“It was a really lucky find,” said Ziegler, “because we weren’t really looking for it. Plus the whole animal came to the surface intact.” Such nets typically damage animals made predominantly of soft tissue, like octopuses. This one, however, was in immaculate condition, an impressive feat considering it was fished from the crushing depth of roughly 4,500 metres.
On board the ship, Ziegler quickly determined that this was an adult male Dumbo octopus, a group of small, deep-sea octopuses. Dumbo octopus species can be identified by the umbrella-like webbing joining their tentacles and their cartoonishly ear-like fins that resemble the oversized ears on Disney’s Dumbo, the flying elephant.
Finding an intact Dumbo octopus is rare. They are the deepest-living octopuses known to science, and they are usually dredged from the deep as fishing bycatch, often too damaged to be identified. To identify an octopus to the species level or to characterise it as a new species typically requires destructive techniques. “You have to look at the internal structure, which would mean disassembling the specimen in order to describe it,” Ziegler said. Instead, Ziegler and Christina Sagorny, currently a doctoral student in Ziegler’s lab, used magnetic resonance imaging (MRI) and micro-computed tomography (micro-ct) scans to non-invasively examine the internal organs and structure of the octopus without making a single cut, except to extract a DNA sample. By using these techniques, Sagorny and Ziegler found that their endearing deep-sea dweller didn’t match any known species. The number of suckers on its tentacles, along with the shape of the gills and beak, suggested something totally new. “Christina was calculating these values and counting the suckers when we realised it didn’t compare to other species,” Ziegler said. “That moment when we realised we were describing a new species, obviously that was a pretty good moment.” The duo named the species Grimpoteuthis imperator, with Emperor Dumbo or Kaiser Dumbo as a proposed common name, because the specimen was discovered along the slopes of the Emperor seamount chain in the
Pacific Ocean.