An international team of scientists just used the UK’s deepest diving vehicle to discover a fish living deeper than any we’ve ever discovered. It looks familiar and bizarre at the same time.

Deploying the Hadal-Lander from the research vessel Falkor above the Mariana Trench — the deepest part of the world’s oceans — the scientists used the vehicle to collect samples along the entire depth range of the trench. That could be anywhere from 5,000 to 10,600 meters (3.1 to 6.5 miles) deep.

This 30-day Hadal Ecosystem Studies (HADES) expedition was meant to catalog the animals, environment, and geology of the deepest part of the oceans. It found a “supergiant amphipod” (think of a massive roly poly bug) and established depth records for other known species of fish. But it also found something that defied complete description.

“This really deep fish did not look like anything we had seen before, nor does it look like anything we know of”, said Dr Alan Jamieson from the University of Aberdeen in a press release.

Found at a depth of 8,145 meters (~5 miles), this odd type of snailfish is now the deepest ocean-dwelling fish we have yet discovered (500 meters deeper than the previous record-holding fish). It has delicate fins, an eel-like tail, a bulbous head, and a “ghostly” body. “It is unbelievably fragile, with large wing-like fins and a head resembling a cartoon dog,” says Jamieson.

The HADES expedition was unique in that it didn’t simply go to the deepest point of the Mariana Trench and sample the environment there. That would give a skewed view of life in the deep ocean by focusing only on arbitrary places like “the deepest,” the scientists contend. Instead, the team made an unprecedented 92 deployments all over the trench, and now have the largest amount of video recorded from these depths — over 105 hours.

To get a better view of this alien world, you have to look at all of it, even if it looks like a dog/eel/tadpole/angel fish.

You can watch a video of the expedition’s findings below:

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READ MORE: University of Aberdeen