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Photograph by Wolcott Henry
Goby fish are some of the smallest vertebrates in the world. This goby fish peers out of a sea anemone in the Solomon Islands. -
Photograph by David Doubilet
Nudibranchs are colorful sea slugs found in reefs and the deep ocean. After mating occurs, lasting from a few seconds to a day, eggs are laid in masses ranging from hundreds to millions. -
Photograph by David Doubilet
Denise's pygmy seahorses are among the smallest fish in the Gasterosteiformes, the most colorful order of fish. These seahorses can be as small as 0.8 inches (2 centimeters) in length. -
Photograph by Tim Laman
Blue ribbon eels can reach up to 51.2 inches (130 centimeters) in length. Mature males are mostly blue, whereas females are completely yellow. Their fleshy nostrils, which resemble fans, make these eels unique. -
Photograph by Tim Laman
A well-camouflaged stargazer fish, which can reach up to 30 inches (75 centimeters) in length, waits for its next meal or hides for protection from predators. They are named stargazers because their eyes appear to be looking skyward. Their protruding jaw has been described as resembling that of a bulldog. -
Photograph by Tim Laman
Nudibranchs feed on a variety of organisms. Some are herbivores that eat algae, while others are filter feeders that take in particles from the water. Most are carnivores that eat many types of animals, including sponges, corals, and worms. This neon-colored nudibranch feeds on a tunicate. -
Photograph by Wolcott Henry
Smooth trunkfish are found in coral reefs. Most trunkfish travel alone or in small groups. They feed on a variety of invertebrates like mollusks, worms, and sponges. They are dangerous to predators—when they get aggravated, toxins are released from their flesh which can kill not only other fish, but also themselves. -
Photograph by Paul Sutherland
The octopus is one of the most intelligent of all invertebrates. Its physical appearance is also unique, with its bulbous head, large, complex eyes, and eight arms. Octopuses vary in size—the smallest is about 2 inches (5 centimeters) long, while the largest species can grow to 18 feet (5.4 meters) in length and have an armspan of almost 30 feet (9 meters).
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