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Enypniastes eximia -

This interesting creature is also known as the Spanish dancer sea cucumber or the headless chicken monster. It has webbed swimming structures that propel it from the ocean floor into water columns, only returning to the ocean floor to feed. With a transparent body, its intestines are visible. They can also be bioluminescent.

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Crinoid - This creature can be found in both shallow waters and in depths up to 29,500 feet (9,000 m). They are best known for their feather-like feeding arms.

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Adults - Mature crinoids are called sea lilies and are attached by a stalk to the ocean floor. When floating, unstalked forms are called feather stars.

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Micromelo undatus - Also known as miniature melo, it is known for its bright blue and white colouring, as well as its brown-lined shell.

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Bubble snail - As a rare bubble snail, it lives on rocky reefs as deep as 16 feet (5 m).

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Austrodromidia octodentata -

Sponge crabs are unlike other crabs: instead of protecting themselves with hard shells, camouflage, or pincers, they prefer to wear sponges on their bodies.

The inspiration for 'SpongeBob SquarePants,' perhaps?

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Psychrolutes marcidus -

The blobfish is arguably the ugliest fish on earth. It is a deep sea fish typically found around Australian and New Zealand coasts.

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Appearance -

Due to decompression damage when brought up from the extreme depth of their habitat, they have a bulbous and gelatinous appearance.

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Achaeus japonicus -

Orangutan crabs are small in size, only 0.7 inches (2 cm), and have a unique rusty-red coat of fine hairs all over their bodies—not too dissimilar from the branch-dwelling orangutans found deep in the jungles of Borneo. 

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Indonesia - Similar to the primate, this crab's name is derived from the Indonesian words for "forest person" (oran hutan). Consider them the forest beings of the sea.

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Pezichthys amplispinus -

Unique to Australia, this fish's "foremost fins are exactly like hands," as described by French mariner Nicolas Baudin in 1802.

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Handfish - Although they come in strange colours and shapes, their hand-like fins are what they all have in common. 

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Ophiuroids - Brittle stars are closely related to starfish and tend to have five long, whip-like arms that can reach up to 24 inches (60 cm).

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Bioluminescence - There are over 60 species of brittle stars that are bioluminescent, including species with green wavelengths and some with blue.

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Pantopoda or pycnogonids -

Commonly known as sea spiders, these creatures are creepier than your average terrestrial arthropods. Just check out their small bodies and extremely long legs.

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Sipuncula -

The peanut worm can grow up to 28 inches (72 cm) in length in some cases, and is most commonly found in shallow waters.

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Megachasma pelagios -

The megamouth shark is a rare and unique species of shark. One was found in Australia—the third ever in history.

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Carapidae family -

There are 31 types of pearlfish. Their slim bodies allow them to live inside the body cavities of invertebrates. Curiously, some species live exclusively in the anuses of sea cucumbers. Delightful!

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Isistius brasiliensis -

Also known as the cookiecutter or cigar shark, it belongs to the dogfish shark family. The shark is known for its feeding habit of biting out round chunks (cookiecutter shape) of fish flesh.

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Bathypterois grallator -

The body of a tripod fish can reach 17 inches (43 cm). What's more, it has long, bony rays below its pectoral fins and tail fin that stretches 3 feet (1 m) in length. And, yes, it stands on its three fins on the ocean floor like a tripod!

See also: The world's best snorkeling destinations

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