Hawaii is home to non-marine and marine gastropods, a scientific class of animals which includes snails. Snails may be identified by their shells, which they use for protection and shelter. Some of Hawaii's non-marine gastropods include the Cookeconcha contorta snail, Pupoidopsis hawaiensis snail and snails belonging to the Godwinia genus of invertebrates. The Cookeconcha contorta snail is endemic to Hawaii and listed as critically endangered on the IUCN Red List. Hihiwi -- a black-shelled snail -- and Newcomb's snail are two examples of marine gastropods, or snails who live in the freshwater lakes and streams within the Hawaiian islands.
Cephalopods are a class of marine-dwelling invertebrates that includes the octopus and squid. Hawaii's cephalopods include the day octopus, crescent octopus, night octopus, bigfin squid and Hawaiian bobtail squid. Cephalopods have large heads -- approximate half the size of their bodies -- and tentacles. Cephalopods are also bilaterally symmetrical, meaning the features on the right and left side of their bodies are identical. These animals are also able to squirt ink; ink squirting is a measure of defense for cephalopods. Octopus and squids are primarily nocturnal animals, meaning they are active at night.
All of Hawaii's crustaceans are members of the phylum Arthropoda. These invertebrates have the ability to live in marine and dry land environments. Some of Hawaii's crustaceans are lobsters, crabs and shrimp. Crustaceans feature jointed appendages on their legs, which are within the crustaceans' exoskeletons -- also known as carapaces. These invertebrates also have antennae and two pincers at the front of their body. The largest crustacean species in Hawaii are the Hawaiian spiny lobsters, which grow up from 13 to 16 inches.
The largest group of invertebrates in Hawaii are insects. This class of invertebrates has a variety of species, such as butterflies, moths, water striders and ants. One species of insects found in Hawaii is the Pacific pelagic water strider. This rare insect lives on the ocean's surface and may also be seen on islands in Southeast Asia. Endemic insects to Hawaii include Blackburn's blue butterfly, which actually has green wings, and two moths -- Aumakua omaomao and Hyles calida. All insects have six legs, exoskeletons, compound eyes and a pair of antennae.