Giant hammerhead flatworms are invading France

The video discusses species of flatworms with shovel-like heads native to Asia, which can grow up to a meter long and reproduce asexually. Citizen sightings have reported at least three hammerhead species in metropolitan France since 1999, with others in overseas territories. These invasive species feed on earthworms, secreting tetrodotoxin to immobilize their prey. This poses a threat to biodiversity as earthworms are crucial for soil aeration and fertility, potentially affecting the ecosystem drastically.

What evidence is there of hammerhead species in metropolitan areas?

Describe the method by which invasive flatworms immobilize their prey.