Hammerhead flatworms are invasive and toxic. These worms, native to Asia, contain neurotoxins similar to those in pufferfish.

Officials said the aggressive species threatens soil structure and can also harm plant roots. Here's how to spot it.

They rank pretty high on the ick factor with their skinny bodies and weird half-moon shaped heads, they're predatory and they are coated with a toxic slime. And they are in East Tennessee. Hammerhead ...

The worms were previously reported in Southbury and may be more active in Connecticut this year.

Denver has a new invasive species, and it looks very similar to your standard earthworm.