Alien-Like Poisonous Worms Invade Texas: Multiply When Halved in Rain

Heavy rains in the Houston, Texas area are causing concerns among residents about the emergence of poisonous, foot-long hammerhead flatworms. These worms, which regenerate when cut in half, secrete toxins that can irritate human skin on contact.

These flatworms thrive in warm, tropical environments and pose a risk to pets if ingested due to their poisonous nature and potential to carry parasites. They often appear on roads, sidewalks, and lawns after rain drives them out from their underground hiding spots.

Experts, including Ashley Morgan-Olvera from the Texas Invasive Species Institute, have advised residents against cutting the worms as a means to kill them because this causes them to multiply. Speaking to KHOU, Morgan-Olvera explained that cutting one worm can lead to the creation of two. Residents are instead encouraged to wear gloves, collect the worms in a plastic bag with salt and vinegar or citrus oil, and freeze them overnight.

People are cautioned to avoid direct contact with these dead worms. If contact occurs, it is recommended to wash the affected area with soap and water immediately, followed by hand sanitizer application.

The hammerhead worm, also known as the arrowhead or shovelhead worm due to its distinct head shape reminiscent of a hammerhead shark, can grow up to 15 inches long. Sometimes mistaken for snakes, these worms are predators to earthworms, which are vital for healthy crops, gardens, and natural ecosystems.

According to Dr. Blake Layton Jr., an entomology expert from Mississippi State University, the hammerhead worm paralyzes earthworms with its toxic slime, then consumes them using its extendable mouth. The same toxin that paralyzes earthworms can also cause skin irritation in humans and sickness in animals. Additionally, these worms reproduce asexually, with parts of their body breaking off and growing into new, genetically identical worms. Dr. Layton described this process as producing a “chip off the old block.”