Lifecycle

Like all true parasites, Anthosoma crassum is dependent upon its fish host for completion of its lifecycle.

  • Females produce a pair of long cylindrical egg strings
    • each containing a single stack of flattened, disc-like eggs.
  • Eggs hatch as nauplius larvae which are 
    • non-feeding 
    • nourished by the yolk they contain
    • generally only 2 nauplius stages in these copepods 
  • the second nauplius larva stage moults into the infective stagethe copepodid.
  • the copepodid locates a host 
    • not known how
    • in related copepods parasitic on fish, host location involves 
      • behaviour that initially brings the larva into the correct habitat to encounter a host, where 
      • larva responds to the presence of a host detected by
        • sensing the mechanical disturbance caused by the host’s swimming
        • or visually as a shadow passing overhead.
  • The final stage of infection , recognising the correct host 
    • usually depends upon detecting chemicals contained in the fish mucus or skin.