A semi-transparent crab about the size of an almond and a tiny, glowing lantern shark are among two new species discovered by Australian scientists exploring the deep sea.

In late 2022, scientists from Australia’s science agency CSIRO embarked on a research voyage in the Gascoyne Marine Park, about 20km (12 miles) off the coast of Western Australia.

Australia is one of the world’s biggest biodiversity hotspots, home to more than a million different species, many of which are not found anywhere else on earth.

But – like much of the globe – large swathes of its water remain unexplored, and the animal and plant life within them unknown to science.

Among the hundreds of specimens collected during the 2022 voyage was the newly described West Australian Lantern Shark. Growing up to 40cm, it has large eyes and a glowing belly, and was found more than 600m below the ocean’s surface.

“Lantern sharks are bioluminescent, with light produced by photophores located on their belly and flanks, which is where their common name comes from,” Dr Will White, a fish scientist, said.

They also discovered a new type of porcelain crab, about 1.5cm in length and found about 122m below sea level. They use hairs to catch food, instead of their claws.

“Porcelain crabs are known as filter feeders, feeding on plankton by using modified mouthparts with long hairs to sweep the water for small pieces of food such as plankton, rather than the typical crab method of grabbing and pinching food with their claws,” said Dr Andrew Hosie, curator of aquatic zoology from the Western Australian Museum.

About 20 new species have been unearthed as a result of the voyage so far, including the Carnavon Flapjack Octopus, a rusty red creature around 4cm big.

Researchers estimate about 600 more are yet to be described and named, as it can take years for scientists to gather the information to prove they’re unique.