Hermit Crab Species Identification

Less than two percent of the 600 species of hermit crabs found throughout the world can be found in the homes of pet owners in the United States: This equates to only seven species, all of which are in the family of crabs known as Coenobita.

  1. Sizes

    • The largest of the hermit crab species found in the United States is the Coenobita brevimanus, the second largest of the Coenobita family. The smallest of the same family is the Coenobita compressus, which grows no larger than 12 mm.

    Exoskeleton Coloration

    • Hermit crabs come in a variety of colors, from common brown, black or white crabs to special species such as the strawberry crab. whose exoskeleton is red with white spots, and the Coenobita rugosus, whose exoskeleton traverses a rainbow's worth of different colors depending on its food supply.

    Pincers and Claws

    • You can tell the type of hermit crab you have by examining its pincers and claws. Some crabs, such as Coenobita cavipes, have large front claws while others like the Coenobita brevimanus, meaning small hand in Latin, have smaller ones. The Coenobita clypeatus can be recognized by its distinctively purple claw. Both the Coenobita rugosus and the Coenobita compressus have stitch marks on their large pincers but the marks on the Coenobita compressus can either be raised or not there at all.

    Shell Preference

    • Most hermit crab species sold as pets in the U.S. use turbo shells to protect their exoskeletons, but the Coenobita cavipe can be distinguished by its preference toward shells that have D-shaped openings.

    Sounds

    • Unlike most hermit crabs that remain silent, the Coenobita rugosus species uses sound as a defense mechanism by rubbing its pincer on its shell to make a bird-like chirping sound when threatened.

    Habitat

    • Most hermit crabs typically live in or near oceans and seas, such as the Pacific Ocean and Caribbean Sea, in community with other hermit crabs; the antisocial exception to this rule is the Coenobita cavipe, which prefers to make its home in the forest. When in captivity, all most hermit crabs need is a tank with sand and a wadding pool to be comfortable, but the strawberry hermit crab also requires humidity and constant temperatures of around 80 degrees C to be comfortable. Private isolation tanks are also necessary for all species of hermit crabs during their molting or shedding periods because they are vulnerable and may be harmed if kept in a tank with another crab.