In pictures: Oceans' tiniest life

The lastest data to be released by the Census of Marine Life (CoML) focuses on "hard to see" species. One of the new creatures to be described by scientists is this "squid worm", recorded at a depth of 2.8km in the Celebes Sea.

Blue/green alga (Image: D Patterson/L Amaral-Zettler/V Egdcomb/MBL)

The diversity of microbes surprised scientists working on the decade-long Census. They say that this blue/green alga belongs to a group that are among the oldest recognisable organisms on Earth, dating back more than three billion years.

Young cephalopod (Image: C Clarke-Hopcroft/UAF/CMarz)

This alien-like creature is a young cephalopod. The term cephalopod is derived from the Greek words "head/feet", and includes squid and octopuses. Although young specimens can look very different from adults, both share arms with suckers and large eyes.

Young tube-anemone (Image: C Clarke-Hopcroft/UAF/CMarz)

Researchers say this larval tube-anemone has already begun fishing for food with the tentacles it will use as an adult, as its dark stomach in the centre of the image suggests it has recently fed.

Juvenille burrower (Image: G Gad/M Buntzow/CoML)

CoML and German researchers described this new species and genus of burrower in 2009. It was more than 4km (2.6 miles) down in the Atlantic's Guinea Basin off the west coast of Africa. This juvenille is only about 0.25mm long.

This transparent pink sea cucumber was spotted during a CoML survey of the Celebes Sea, in the western Pacific. Researchers think it may be a new species, but requires a specialist to examine an actual specimen.

Acantharian (Image: L Amaral-Zettler/MBL)

Scientists say acantharians are one of the four types of large amoebae that occur in marine open waters. Their skeletons are made of a single crystal of strontium sulphate, which quickly dissolves in the ocean water after the cell dies.