Anchor Worm

Natural Habitat

Freshwater environments such as ponds, lakes, and aquariums, attached to the skin, fins, or gills of fish hosts.

Diet & Feeding

Parasitic; females use specialized mouthparts to burrow into the host fish's flesh to feed on blood and tissue fluids.

Behavior Patterns

Adult females are permanent ectoparasites that lose most of their crustacean features. They undergo multiple larval stages (nauplius and copepodid) before mating. After mating, the female burrows into a fish host, while the male dies.

Risks & Benefits

Pathogenic to freshwater fish; causes inflammation, secondary bacterial or fungal infections, and can lead to host mortality. They offer no known benefits to the ecosystem and are considered a major pest in aquaculture.

Identified on: 1/3/2026