Microscopic marine life

Microbes: Chlamydophrys, a little reported amoeba inside a house called a test, usually has one large nucleus and forms clusters as in this group of 10.
Ocean explorers have made an inventory of the ocean species that are hardest to see, yet together underpin almost all other life on Earth. The study has been carried out as part of the Census of Marine Life, a huge 10-year project involving researchers in more than 80 nations that aims to chart the diversity, distribution and abundance of life in the oceans
Photograph: D. J. Patterson, L Amaral-Zettler, M. Peglar and T. Nerad/MBL

Microbes: Eutreptiella is a marine euglenid with chloroplasts and characteristic eyespot. Euglenids are distinguished, in part, by the ridges under the cell membrane.
Scientists say that identifying species within these hard-to-see groups, where they are and in what numbers, and the environmental role of each, is critical for understanding the size, dynamics and stability of Earth's food chain, carbon cycle and other issues
Photograph: D. J. Patterson, L. Amaral-Zettler and V. Edgcomb/MBL

Microbes: This is a sample from a salt marsh in Massachusetts and shows a collection of bacteria. The darkest ones are Beggiatoa, a colourless sulphur bacterium which accumulates elemental sulphur and this makes the cells opaque or refractile. The large pink ovoid is a cell of Chromatium, a purple sulphur bacterium, the green is a cyanobacterium, Lyngbya
Photograph: D. J. Patterson, L. Amaral-Zettler and V. Edgcomb/MBL

Microbes: Cryptopharynx is one of the cuter little ciliated single cells with a small protruding mouth. This cell was collected from the same Massachusetts salt marsh at Little Sippewissett
Photograph: D. J. Patterson, L. Amaral-Zettler and V. Edgcomb/MBL

Microbes: The acantharians are one of the four types of large amoebae that occur in marine open waters. Their fragile skeletons are made of a single crystal of strontium sulfate that quickly dissolves in the ocean water after the cell dies
Photograph: MBL

Microbes: Ceratium longipes, a representative of a large and distinctive group of marine photosynthetic dinoflagellates adorns itself with three horns
Photograph: David Patterson, Linda Amaral Zettler, Mike Peglar and Tom Nerad/MBL

Microbes: Bacteriastrum, found as a fairly abundant member of the surface phytoplankton community in a plankton-net sample taken off Martha's Vineyard in Massachusetts, US. Constituting 50-90% of all ocean biomass, marine microbes are the tiniest cogs essential to planetary functioning
Photograph: J. Cole/MBL

Microbes: Lyngbya is a filamentous blue-green alga (cyanobacterium) that usually has many cells joined together. They are often motile, gliding through the substrate. These algae are probably the oldest recognisable organisms on Earth - traceable back to the earliest fossils, over 3bn years old
Photograph: D. J. Patterson, L. Amaral-Zettler and V. Edgcomb/MBL

Microbes: A thin section of a core of a microbial mat from Baja California. It shows the layering of the microbial communities. The dark region in the middle is a zone to which oxygen has not penetrated
Photograph: D. J. Patterson/MBL

Microbes: Pyrocystis, a nonmotile, bioluminescent dinoflagellate. This cell is undergoing cell division, and two nuclei are located above and below the central knot of plastids
Photograph: Bob Andersen and D. J. Patterson/MBL

Microbes: The Lost City hydrothermal vent field in the mid-Atlantic Ocean. Each gram of the enormous carbonate structures house up to one billion cells. Tents release methane and hydrogen into the surrounding water
Photograph: NOAA/MBL

Microbes: These pink bubbles are live planktonic foraminifera from the Sargasso Sea, a group of single-celled animals that produce multi-chambered tests to protect their jelly-like bodies. The red line is 200 microns long (or 0.2 mm); the forams are about 0.5mm in diameter
Photograph: Colomban de Vargas, EPPO/SBRoscoff/MBL

Larvae: Most fish start out as eggs and pass through a larval stage, with hundreds or thousands of eggs produced in many species. This egg is ready to hatch, and the larvae it produces will start dining soon on zooplankton
Photograph: Russ Hopcroft/UAF/CoML/MBL

Larvae: Although adult echinoderms (sea stars and kin) we are used to seeing have radial symmetry, their larvae start out with bilateral as do most vertebrates. These larval brittle stars are an important pelagic stage for dispersal of their bottom-bound parents. They capitalize on the abundance of food in the plankton to support early growth prior to metamorphosis and settlement to the sea floor. This pair is just over 1mm across, and tend to be found in the upper ocean, most commonly over continental shelves
Photograph: Russ Hopcroft/UAF/CMarZ/MBL

Larvae: The larval spider crab uses the numerous spines on its body to deter predators, but more importantly to increase its drag in the water to keep it from sinking, much like a parachute does. Like other larval phases, it is important both as a dispersal phase, and to take advantage of the abundant food in the plankton
Photograph: Cheryl Clarke-Hopcroft/UAF/MBL

Larvae: The zoea is the first larval stage of a crab, often with prominent spines to make it less attractive prey to larval fish
Photograph: Russ Hopcroft/UAF/CoML/MBL

Larvae: An earlier stage of the larval tube-anemone, this specimen looks as if it has a smiling face inside. The common types of sea-anemones spend little, if any, time in the plankton, as compared to tube-anemones which spend much longer and appear to feed while there
Photograph: Cheryl Clarke-Hopcroft/UAF/CMarZ/MBL

Larvae: The larvae of many deep-sea fish are virtually unknown. This rare find of an angler fish larva caused great joy when it was discovered mixed in with a zooplankton sample
Photograph: Cheryl Clarke-Hopcroft/UAF/CMarz/MBL

A squid worm, collected in the Celebes Sea at about 2800m depth. It is considered a new genus and species, in a newly described family of swimming polychaetes
Photograph: L. Madin/WHOI/MBL

Burrowers: Census of Marine Life scientists with the German Centre for Marine Biodiversity Research at the Senckenberg Research Institute, last year described this new species and genus of the burrower loriciferan, Culexiregiloricus trichiscalida, found at 4,141m depth in the Atlantic's Guinea Basin, south of Cote d'Ivoire. Loriciferans, affectionately dubbed 'girdle wearers' due to characteristic hind shells resembling a corset, are among the smallest known multi-cellular marine animals. This is a juvenile stage specimen with a body length is about 0.25 of a millimetre – roughly the width of three human hairs. The body is filled with granular cells and tissue
Photograph: Gunnar Gad, Marco Büntzow, Deutsches Zentrum für Marine Biodiversitätsforschung/German Centre for Marine Biodiversity Research,/MBL

Zooplankton: Rosacea tentacles extent metres away from the main body and contract when disturbed by potential food items. The beads are stinging cells that immobilize and kill the prey
Photograph: L. Madin/WHOI/MBL