Small, ghostly-white octopus was found in the deep sea off Hawaii and has been likened to the beloved cartoon character.

An underwater research craft has spotted a "ghost-like" octopus that appears to belong to a previously unknown species on the ocean floor near Hawaii, a discovery that highlights how little is known about the deep sea, a U.S. zoologist.

The milky white creature, nicknamed "Casper the Friendly Ghost" by Twitter users, was caught on cameras mounted on the craft as it explored the Pacific Ocean at a depth of 4,290 metres, the National Oceanic and Atmospheric Administration said.

Describing the animal as an incirrate octopod, one of two main groupings of octopods, NOAA said it was the first time an incirrate was spotted so deep in the ocean. "This animal was particularly unusual because it lacked the pigment cells, called chromatophores, typical of most cephalopods, and it did not seem very muscular," said Michael Vecchione, a research zoologist at NOAA's National Marine Fisheries Service.

Source: cbc.ca, abcnews.go.com, noaa.gov