Recent heavy rains in the Houston area have led to an increase in sightings of the hammerhead flatworm, an invasive species known for its toxic properties and remarkable ability to regenerate when cut. These foot-long worms secrete toxins that can cause skin irritation in humans and are poisonous to pets if ingested.
An Invasive Menace
The hammerhead flatworm, also known as the shovelhead or arrowhead worm, is typically found on lawns, sidewalks, and roads following rainstorms. These creatures thrive in hot and humid climates and pose a significant risk to both people and animals due to their toxic slime.
Ashley Morgan-Olvera, M.S., from the Texas Invasive Species Institute, highlighted the worm’s regenerative abilities: “If you chop it into two pieces, you get two worms,” she told KHOU. As a result, residents are advised to avoid touching the worms directly. Instead, they should use gloves and place the worms in a plastic bag with salt, vinegar, or citrus oil before freezing them overnight. Even after the worm is dead, handling it with bare hands is not recommended; if contact occurs, wash the area with soap and water, and apply hand sanitizer.
Distinctive and Dangerous
Hammerhead flatworms get their name from their unique head shape, reminiscent of a hammerhead shark. They can grow up to 15 inches long and are sometimes mistaken for snakes. Their toxic slime, which they use to paralyze earthworms, is particularly dangerous as it causes skin irritation in humans and can make animals sick.
Dr. Blake Layton Jr., an entomology expert at Mississippi State University, explains that the worm’s “mouth” extends to digest earthworms after coating them with toxic slime. This predatory behavior disrupts ecosystems, as earthworms are crucial for maintaining healthy soil in crops, gardens, and natural environments.
Reproductive Threats
Hammerhead worms also pose a threat due to their ability to carry parasites and their asexual reproduction, which produces genetically identical offspring. “A portion of the rear of the worm breaks off and grows a new head, producing a new flatworm genetically identical to its parent,” Dr. Layton Jr. explains. This rapid and effective method of reproduction means a single hammerhead worm can quickly multiply, spreading its toxic slime and potential parasites throughout an area.
As Texas residents deal with the aftermath of heavy rains, the emergence of these giant, poisonous worms adds an unexpected and hazardous challenge to maintaining safe and healthy environments.