Oarfish 
Regalecus glesne
phylum Chordata
Once mistaken for a sea serpent, the oarfish is the longest bony
fish, over 50 feet (17 m). The name refers to red fins that pivot
as it swims, like oars on a boat §.
illustration © E. Paul Oberlander
Chelonia mydas
phylum Chordata
Sea turtles have an uncanny sense of direction; some migrate over
a thousand miles to lay eggs. Like most sea turtles, green
turtles are threatened by hunting and habitat loss.
photo © Tom Campbell
Meiofauna
These animals--all less than a millimeter long--live between sand
grains. Meiofauna samples from a single bucket of sand taken off
Florida may yield up to 22 phyla. The world's rain forests have
15 to 16 phyla of all kinds of organisms at most §.
illustration © Robert Higgins
Thelenota rubralineata
phylum Echinodermata
Like other sea cucumbers (relatives of sea stars and urchins),
this species can shoot sticky poisonous tubular threads from its
anus. The writhing tubules entangle an attacker, while the
"victim" escapes to regenerate new tubules §.
photo © Mary Jane Adams
Phyllopteryx taeniolatus
phylum Chordata
Sea dragons reverse traditional sex roles. The male carries and incubates the eggs, which the female lays in a soft skin pouch under his tail. He stores the eggs until they hatch §. photo © Fred Bavendam
Dasychalina cyathina
phylum Porifera
None of the five thousand or so species of sponges has
specialized tissue. They simply filter water through pores in
order to "eat" detritus and plankton §.
photo © David Wrobel
Chrysaora sp.
phylum Cnidaria
Many marine animals remain to be discovered. This relative of
corals and sea anemones was found in the early 1990s. Formal
scientific identification of the species hasn't been published.
photo © Bob Cranston
Pleurobrachia bachei
phylum Ctenophora
If disturbed at night, sea gooseberries (and other comb jellies)
glow in the dark. At sea, people have reported waters filled
with greenish comb jelly "fireworks." Even the embryos of this
group light up §.
photo © David Wrobel
Clownfish and anemonephylum Chordata and phylum Cnidaria
The mobile fish draws predators; the non-mobile anemone kills
them with its stinging cells. The anemone eats; the fish gets
leftovers and protection §.
photo © Michele Hall/HHP
phylum Nematomorpha
These are marine members of a mostly fresh-water group (their
name comes from having been discovered in watering troughs).
These parasites absorb nutrients through their body walls §.
photo © Oxford Scientific Films/Animals Animals
Lepas anseripera
phylum Arthropoda
Larval barnacles can swim, but adults use environmental cues to
choose a hard surface for settling down. "Glued" in place, a
barnacle stands on its head and uses its foot to scoop water (and
food) into its mouth §.
photo © Oxford Scientific Films/Animals Animals
Vent worms
Riftia pachyptila
phylum Vestimentifera
Found only around sea-floor cracks, vent worms live in sulfurous hot water and rely on bacteria living in their body tissue for energy. Adults of this group do not have a mouth or digestive tract §. photo © Al Giddings/Images Unlimited, Inc.
Peanut worm
Cloeosiphon aspergillus
phylum Sipuncula
The name comes from the shape they assume when they contract.
Adults burrow in sand or dwell in crevices in rocks or coral.
The long-lived larvae swim in warm surface waters the world
over §.
photo © Kathie Atkinson/Oxford Scientific Films/Animals Animals
Polychaetes
Chloeia viridis
phylum Annelida
For reproducing, many "bristle worms" have split personalities.
They develop an extra body part containing sex cells (and even
"eyes" and "feet" for swimming), which breaks off, rises to the
surface, and releases the cells §.
photo © Woody Lee, Smithsonian Marine Station
Brachiopods
Laqueus californiensis
phylum Brachiopoda
Often called lamp shells because of their resemblance to
Aladdin's lamp, this ancient group has been around at least 400
million years, with 26,000 species in the fossil record. Only
335 species survive today §.
photo © David Wrobel
Pencil urchin
Heterocentrotus mammillatus
phylum Echinodermata
Sea urchins maintain ecological balance in coral communities by
devouring algae that could outcompete the corals. Thick spines
help stabilize the urchin in rough waters §.
photo © Bob Cranston
Arrow wormsphylum Chaetognatha
Billions of these small predators live in the upper layer of open
seas. Named "hairy jaws," they have movable hooks to grasp and
swallow prey--young fish, protists, copepods §.
photo © Peter Parks/Oxford Scientific Films/Animals Animals
Sea grass and kelp
Phyllospadix scouleri and Eisenia arborea
phylum Angiospermophyta (grass)
phylum Phaeophyta (kelp)
In the oceans, algae far outnumber flowering plants. The surf
grass on the left is a flowering plant. The kelp on the right is
a brown alga §.
photo © Jeff Rotman
Sea-star larva phylum Echinodermata
Many immature marine invertebrates (which may not even look like the adults of the same species) drift over long distances §. This swimming sea-star larva will become a bottom-dwelling adult. photo © Peter Parks/Oxford Scientific Films/Animals Animals
Dinoflagellates
Ceratium
phylum Dinoflagellata
Some of this group of one-celled, mostly planktonic organisms are
plant-like and
photo © synthetic; others are animal-like and "eat"
food. Some produce potent neurotoxins and may cause red tides
that kill animals §.
photo © E. R. Degginger/Animals Animals
Brown algae
Macrocystis pyrifera
phylum Phaeophyta
For size, giant kelp has no rivals among sea plants and algae--it
can grow to lengths of 260 feet (80 m) or more. Upper fronds,
exposed to the most sunlight, can grow up to 2 feet (0.6 m) in a
day §.
photo © Helmut Horn
Red algae
Maripelta rotata
phylum Rhodophyta
Red algae grow from the intertidal zone down to 900 feet (274
m) §. Their color allows them to absorb the parts of sunlight
that penetrate deeper water. Agar (used to culture bacteria)
comes from a species of red algae §.
photo © David Wrobel
Radiolarians
Sarcodina radiolarida
phylum Actinopoda
With their elaborate skeletons of silica, these single-celled
organisms are often preserved on the sea floor after they die.
Buried in sedimentary rock layers, they mark changes in oceanic
conditions §.
photo © Al Giddings/Images Unlimited, Inc.
Foramsphylum Foraminifera
Almost all of the 40,000 known species are fossils and
microscopic. The white chalk cliffs of Dover, England, are
deposits of calcium carbonate foram shells. Some forams are good
oil-deposit markers §.
photo © Peter Parks/Norbert Wu
Blue-green algae
Oscillatoria
phylum Cyanophyta
These photosynthesizing bacterial cells may have released oxygen
into the primordial atmosphere §. Although most are blue-
green, one can appear red--it colors the Red Sea §.
photo © Sinclair Stammers/Science Photo Library/Photo Researchers,
Inc.
Blue whale
Balaenoptera musculus
phylum Chordata
Larger than any animal ever (including dinosaurs), the blue whale
has a heart the size of a car. An adult sucks in 45 tons of
water in a gulp, and filters out 3 to 4 tons of small shrimp and
fish daily §.
photo © Doc White/Ocean Images, Inc.
Sea hare
Aplysia sp.
phylum Mollusca
Sea hares, unlike their relatives the snails, don't have shells.
Instead, they release purple ink for escape and toxic white fluid
for protection when disturbed §.
photo © Mike Severns/Tom Stack & Associates
Xenophyophores
Reticulammina labryinthica
phylum Xenophyophora
These giant single-celled organisms can be seen by the naked eye,
yet little is known about them. They've been found only on the
sea floor. In some Pacific trenches, half the bottom is covered
by slime they produce while feeding §.
photo © Institute for Oceanographic Sciences Deacon Laboratory
Diatoms
Pleurosiama balticum
phylum Bacillariophyta
The remains of billions of silica diatom shells have made
history--geologic, biological, and even industrial. Alfred Nobel
used diatomaceous earth to stabilize nitroglycerine when he
invented dynamite §.
photo © Peter Parks/Norbert Wu
Sea otter
Enhydra lutris
phylum Chordata
Sea otters help to keep kelp healthy by eating the sea urchins
and abalones that graze on kelp. When 19th-century hunting
almost wiped out California sea otters, grazers destroyed giant
kelp in some areas §.
photo © Tom Campbell
Marine viruses viruses don't belong to a phylum
These bits of genetic material coated with protein aren't really
living organisms (they can't reproduce outside of host cells--
mostly bacteria). From 50,000 to 50 million marine viruses can
be found in a teaspoon of sea water §.
electron micrograph © John Waterbury, Woods Hole Oceanographic Institution
Ocean Planet Exhibition Floorplan
gene carl feldman (gene@seawifs.gsfc.nasa.gov) (301) 286-9428
