A pelagic, or open-ocean, octopus gives off a neon glow in Hawaii.
Most species of octopus have no internal skeleton, unlike other cephalopods.
A photographer's strobe gives a violet sheen to this translucent juvenile roundbelly cowfish off the coast of Kona, Hawaii.
Also known as the transparent boxfish, the roundbelly cowfish has two short horns in front of its eyes.
A hydromedusa spreads its luminescent tentacles in the Weddell Sea near Antarctica
Tiny marine snails known as sea butterflies take many forms, including heart-shaped,
such as this species in Antarctica's Weddell Sea.
A nearly translucent squid glows in reds and purples.
There are nearly 300 different species of squid, found in oceans worldwide
Darkness in Antarctica's Weddell Sea gives this comb jelly a chance to
show off its candy-colored bioluminescent cells
Antarctic krill, such as this specimen in the Weddell Sea with a stomach full of yellow algae,
are a critical link in the ocean food web
The flower-shaped larva of a scyphomedusa jelly drifts in Antarctica's Weddell Sea
A tiny jellyfish, with tentacles folded and its orange central mass visible through its transparent body,
drifts in the waters of Antarctica's Weddell Sea.
A transparent larval shrimp piggybacks on an equally see-through jellyfish in the waters around Hawaii
Flounder in their larval stage, such as this one in Hawaii,
resemble ghostly undersize replicas of adults