Reproduction
Anatomy
Background
Enviornmental Interactions
Fun Facts
100

What family is the hammerhead worm apart of?

Geoplanidae

100

What shape is the head of a hammerhead worm?

A flattened semicircle (looks like a hammer)

100

where did they come from?

Southeast Asia

100

What do hammerhead worms eat?

Earthworms and other soil-dwelling invertebrates

100

What color are most hammerhead worms?

Brown, yellow or greenish with dark stripes

200

How do hammerhead worms asexually?

Fragmentation

200

what organ do hammerhead worms use to move?

their creeping sole

200
How did they get to the USA?

transported in the soil of imported plants and landscaping materials

200

What effect do they have on earthworm populations?

they are reducing native earthworm numbers 

200

What toxic chemical do they release?

Tetrodotoxin (also found in pufferfish)

300

How do hammerhead worms reproduce sexually?

they are hermaphrodites and exchange sperm with another worm before laying eggs

300
Why is their pharynx important during consumption?

it extends from their body, releasing digestive enzymes, and sucks up their liquefied prey

300

What did they evolve from?

other flatworm species 

300

How do they disrupt the soil?

they slow the nutrient cycling process by killing the earthworms

300

How long can a hammerhead worm survive cut in half?

Each half can regenerate into a full worm within about 2 weeks
400

What factors trigger their reproduction?

warm temperatures, high humidity, and abundant food supply

400

How does their mucus help them survive?

It prevents them from drying out and helps them move easier

400

What habitat do they prefer to live in?

moist, shaded soil enviornments like gardens and forests

400

How do they protect themselves from predators?

they excrete a toxic mucus containing tetrodotoxin (very toxic) to make them inedible 

400

What makes them an example of an invasive species that can harm biodiversity?

They outcompete native species, reproduce rapidly, resist pesticides and can self-reproduce

500
Why is their method of reproducing a pain when trying to exterminate them?
their small body fragments can grow into new worms, so cutting or crushing them just increases the amount of worms.
500
How does their anatomy allow them to regenerate lost body parts?

They have neoblast stem cells that can turn into any type of cell

500

What are these worms known for?

having a hammer shaped head and being able to regenerate lost body sections
500

Why are they bad for the US envoirnment?

they disrupt soil ecosystems, potentially leading to declines in native species and impacting soil composition and nutrient cycling

500

How long can they grow to?

over a foot!