One of the most colorful of all the marine arthropods, the peacock mantis shrimp (Odontodactylus scyallarus) has garnered a certain amount of media attention in the scientific community for a number of reasons. Contrary to its name, it is not an actual shrimp, but it is a crustacean, in the same sub-phylum as lobsters, crabs, and shrimp. The eyes of peacock mantis shrimp are mobile, compound eyes that see not only in color but in some ultraviolet shades as well; they are the only animals in the world with hyper-spectral vision. These eyes are an important asset to the species, as they allow it to see approaching prey very easily.

When its prey is within reach, this mantis shrimp shoots out one of its enormously powerful front legs at a velocity of 120 kilometers per hour and up to 100 times the force of its own body weight. This force is generated by a joint in the legs that acts like a spring. It is strong enough to break aquarium glass and it allows this mantis shrimp to take on prey larger than itself, such as other crustaceans and mollusks. Like other mantis shrimp, they live in burrows on the ocean floor and in crevices in rocks, which can lead to their accidental transportation to aquariums.

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Photos © Ryan Photographic

This adorable spider is commonly known as the peacock spider (Maratus volans), for obvious reasons. Similar to actual peacocks, male peacock spiders raise a colorful flap on their abdomens to garner female attention. Also common among this species is a sort of spider polygamy where male peacock spiders court multiple females at once.