Lady crab (Charybdis japonica)

Key features

  • 5 distinct spines on upper surface of foreclaw
  • 6 spines on each side of eyes
  • Swimming paddles on last set of legs
  • Red/purple/orange to pale green & off-white shell
  • Shell up to 12 cm wide


  • Mobile; found on or buried in firm, fine sand or mud
  • Subtidal to 15 m depth
  • Estuarine & marine areas


  • Can carry White Spot Syndrome virus which can devastate native & farmed prawns, crabs & lobsters

Known locations

  • Not yet in Australia

What you can do

  • Inspect & clean niche areas & antifoul your vessel regularly
  • Clean & dry equipment before transporting & using in a different location

Learn more

Read the national biofouling management guidelines for your sector.

Report immediately Outside known locations!

  • Note the exact locations
  • If possible, collect a sample and freeze in a plastic bag or take a photo
  • See for your state contacts

Report a sighting

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