Signal Crayfish
Pacifastacus leniusculus
This record describes Pacifastacus leniusculus (species). Recorded family: Astacidae. Recorded order: Decapoda.
Identification and Appearance
Classification
About Crabs, Crayfishes, Lobsters, Prawns, and Shrimp: the wider group
Order-level background for Decapoda, the group containing Pacifastacus leniusculus. 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 Signal Crayfish (5)
Photo credits: Contributed by Eric Moody