Invertebrates

FEATURES

Article
Zombie worms don’t crave brains: instead they seek bones. The 1 to 3 inch (2 to 7 centimeter) Osedax worms were first discovered living in the bones of a rotting gray whale on the...
Marine parasites may be small in size, but they can be present in very high...
During the summer of 1998, scientists at the Virginia Institute of Marine...
The blanket octopus can rip a poisonous tentacle from a Portuguese man-o-war...

LATEST POSTS

Like this ctenophore ( Aulococtena acuminata ), many animals that live in the midwater zone are red—making them almost invisible in the dim blue light that filters down from the sea surface. This small comb jelly snares prey with...
Sponges are animals that eat tiny food particles as they pump water through...
Polarized sunglasses have become the norm for humans when they want to...

LEARN MORE

Giant squid live up to their name: the largest giant squid ever recorded by scientists was almost 43 feet (13 meters) long,...

The Ocean Blog

Sample the surprising diversity of deep-sea corals. See some of the ways they differ in color, shape, and size. Explore more in the multimedia feature " Coral Gardens of the Deep Sea ."
It's a pygmy seahorse ( Hippocampus bargibanti ), found in Indonesia's biodiverse Coral Triangle and one of the smallest seahorse species in the world! They can change colors like a chameleon to...
Two bright orange anemonefish ( Amphiprion ocellaris ) poke their heads between anemone tentacles. Anemonefish are able to swim amongst the stinging tentacles without getting stung — but no one knows...
A cnidarian brought up from the Arctic seafloor more than 2000 meters (6562 feet) deep.
Ari Daniel Shapiro is joined for this episode of One Species at a Time by serious beachcombers along the high-tide line of Sanibel Island, Florida. These “shellers” come in search of beautiful sea...
A longshoreman stands in front of a large pile of oyster shells on waterfront pier in Atlantic City in 1910. Back then, oysters were incredibly abundant. In the late 1800s, fishermen pulled in 10...
This close-up view of salps, which have aggregated together into a long chain, have brilliant red guts from eating red plankton. They were observed by researchers with the Census of Marine...
As it clings to a red sea fan, a feather star ( Cenometra bella ) gently waves its slender arms—filtering bits of food from the water. Also known as sea lilies, feather stars are related to sea stars...
Not all slugs (snails without shells) are slimy brown pests found in your backyard garden. In the ocean they come in a huge variety of colors — some match the background and are hard to spot, but...
The spiral-tufted bryozoan ( Bugula neritina ) is being studied for a potential Alzheimer's disease and cancer drug -- but it's not the bryozoan that makes the chemical. The chemical, found in the...
Rudist clams are mollusks that went extinct about 65 million years ago. They were the reef builders of the Cretaceous Period, the heyday of the dinosaurs. Today corals have taken over the role...
This pair of sea butterflies ( Limacina helicina ) flutter not far from the ocean's surface in the Arctic. Sea butterflies are a type of sea snail, but instead of dragging themselves around the...
This image from a scanning electron micrograph magnifies the tiny teeth that cover the surface of the giant squid’s tongue-like organ, or radula . Seven rows of sharp teeth help direct tiny pieces of...
Brachiopods are an ancient group of organisms, at least 600 millions years old. They might just look like clams, but they are not even closely related. Instead of being horizontally symmetrical along...
The whitish spots on this fish are individual parasitic trematode worms. Trematodes have complicated life cycles that usually involve multiple hosts -- often starting in a snail and then moving on to...
A small horseshoe crab ( Limulus polyphemus ) rests on seaweed in Stage Harbor, Massachusetts. Atlantic horseshoe crabs can be found along the coast of North America from the Yucatán Peninsula to...
Dr. Clyde Roper recounts the tale of his encounter with a giant squid specimen ( Architeuthis dux) that was found washed up on a Massachusetts beach in this excerpt from "Eyeball to Eyeball," an...
From the giant squid to microscopic squid babies, squids are beautiful and fascinating. As cephalopods, the same family as octopuses and cuttlefish, they have no bones, and swim head-first through...
Subscribe to Invertebrates