It looks like the slippery dick finally has a challenger for the title of fish with the most ridiculous common name. Introducing the bony-eared assfish (Acanthonus armatus).

The bony-eared assfish ... it's a looker. Royal B.C. Museum/used with permission. 

Despite being just 30 centimetres long, the tiny specimen made a big splash at Victoria's Royal B.C. Museum, where it landed after being hauled up by scientists nearly ten years ago. 

Assfish are members of the cusk-eel family, a group of eel-like bony fish found only at extreme depths. They're known to inhabit the Pacific, but before this sighting, one had never been seen in North America. 

"When we first found the fish there were six or seven of us on the deck of the boat looking at it, and nobody could even guess which family it belonged to, because we had just never seen one before," curator of vertebrate zoology Gavin Hanke told CBC. 

It's a looker, no doubt, but like the mighty blobfish, assfishes (I don't think I will ever tire of saying that) don't always appear this unalluring. Undergoing to the immense change in pressure from seafloor to surface causes the fish's cells to expand, turning sleek skin into a gooey, gelatinous mess.

In relation to body size, cusk-eels like the assfish have the smallest brains of any teleost fish, and quite possibly any vertebrate – but this one won't be opened up any time soon. Because it's unique to the area, the team plans to keep the specimen intact and on display. 

When you live 1,171 to 4,415 metres (3,842 to 14,485 ft) below the surface, both food and light are scarce commodities. Saving energy is key to survival, so the fish spend their days hovering just above the seafloor, waiting patiently for prey to pass by. It's because of this slow lifestyle that the fish are able to operate on very little brain power. 

Impressive as it may be, this assfish isn't the deepest-diving cusk-eel. Back in 2014, scientists managed to film one a whopping 8,143 metres (26,722 feet) into the Mariana Trench. (For a bit of perspective, Mount Everest is 29,029 feet tall.)


Top header image: Royal B.C. Museum/used with permission.