Scientists say they recently captured "supergiant" deep-sea crustaceans nearly a foot long -- the likes of which have rarely been seen -- in an ocean trench off New Zealand.

The seven amphipods measure about 28 centimeters (about 11 inches) long, which is 10 times the length of normal deep-sea amphipods and nearly three times the size of what are considered giant amphipods, Scotland's University of Aberdeen said Thursday.

They are the biggest whole specimens of supergiants ever recorded, according to the university.

The team's deep-sea cameras also caught footage of a supergiant that scientists estimated was about 34 centimeters (13 inches) long.

Though the creatures may remind observers of shrimp, amphipods are an order apart.

Scientists with the university and New Zealand's National Institute of Water and Atmospheric Research were looking for deep-sea snailfish when a trap made the unexpected catch.

"(After) the traps came on deck ... I stopped and thought, 'What on Earth is that?' whilst catching a glimpse of an amphipod far bigger than I ever though possible," the voyage's leader, Alan Jamieson of the University of Aberdeen's Oceanlab, said in a news release. "It's a bit like finding a footlong cockroach."

The capture was made about 7 kilometers (more than 4 miles) below the surface, the deepest point that supergiants have been found, the university said.

Supergiants were found a few times off Hawaii in the 1970s and 1980s but haven't been reported since, according to the university.

The scientists will now try to determine whether the species they caught are the same as those found off Hawaii decades ago.