Japanese Shore Crab
Hemigrapsus sanguineus
This record describes Hemigrapsus sanguineus (species). Recorded family: Grapsidae. Recorded order: Decapoda.
Identification and Appearance
Often found with another invasive species, Carcinus maenas .
Classification
Habitat and Range
Habitat
Intertidal
Geographic Range
Introduced from Asia; now established along the Atlantic coastline from Maine to North Carolina.
About Crabs, Crayfishes, Lobsters, Prawns, and Shrimp: the wider group
Order-level background for Decapoda, the group containing Hemigrapsus sanguineus. Species-specific details appear above.
Group overview
Decapoda includes ~15,000 described species of crabs, lobsters, shrimp, and crayfish. Although primarily marine and freshwater, some species like hermit crabs and coconut crabs are fully terrestrial.
Ecological role of the group
Crayfish are keystone species in freshwater ecosystems, influencing water clarity, sediment dynamics, and plant communities. Hermit crabs play vital roles in nutrient cycling on tropical islands.
Economic and practical significance of the group
The global shrimp industry alone is worth over $45 billion annually. Crayfish are important aquaculture species and invasive crayfish cause ecological damage estimated in the hundreds of millions annually in Europe and North America.
Recorded sources for this group: FAO fisheries statistics, freshwater ecology. Imported estimates may describe particular regions or reporting periods.
Photos of Japanese Shore Crab (5)
Photo credits: Contributed by Steve Nanz; Additional contributions by KenW , metrioptera