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Hammerhead Worm

Bipalium sp


Known loosely as Hammerhead Worm because of the distinctive shape of their head region, they are predators of earthworms. They easily track the earthworms by following their trails, then they secrete a sticky fluid and hold the prey in place with their muscles. Once the hammerhead worms start eating, things become even more disturbing. They first push their pharynx out of their mouths, then they cover the earthworm with the neurotoxins they secrete. This chemical, known as tetrodotoxin (which is also found in such animals as pufferfish and triggerfish), cause the earthworms to be paralysed. They then releases enzymes which cause the earthworm's body to liquefy and the Hammerhead worms will then externally digest the earthworm. Hammerhead worms are the only terrestrial invertebrates with this ability. The hammerhead worm essentially sucks up the dissolved earthworm. The digestion process mostly occurs outside of the hammerhead worm’s body, since the earthworm’s flesh is already in liquid form!


Tropical rainforest.

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Hema a year ago

That is the last thing I want to see is a poor earthworm being liquidated.

AlbertKang a year ago

Thanks, @armadeus.4 :)

Yes, @Christine Y :D
Earthworm smoothie will be one healthy smoothie, full of proteins!

Christine Y.
Christine Y. a year ago

Earthworm smoothie ;P

armadeus.4 a year ago

That's nuts! Fantastic spotting Albert. Thank you for sharing :)

AlbertKang a year ago

Thanks, @Hema for the info and link to your Spotting. Interesting info.

I don't see them in the many in most of my night walks and leave them be, they are part of the nature and there is no outbreak of them. However, I would love to see them 'catching and feeding' on an earthworm though.

Hema a year ago

these worms are almost impossible to destroy.Marine creatures might be capable of eating them.I found one a long time ago.Was fascinated and we had a big discussion ! I also found a headless one next to it and that worm was navigating itself perfectly.

burnsscitech544 a year ago

I the wiggles thing

AlbertKang a year ago

Thanks, @shebebusynow for sharing your thoughts.

Thanks a lot, @Daniele for correcting, will update the info,
I got the info from another website (non-scientific), so I guess the information from the link you provided is more reliable :D

DanielePralong a year ago

Great images Albert! I would have some qualification to your description:
Tetrodotoxin is a neurotoxin that causes paralysis; it does not cause liquefaction. Liquefaction itself is produced by the hammerhead worm's digestive enzymes. A 2014 study has shown the presence of tetrodotoxin in two Bipalium species (Bipalium adventitium and Bipalium kewense). This provides strong evidence suggesting that tetrodotoxin is used during predation by these 2 species. However the study did not directly document the actual secretion of tetrodotoxin or confirm the role of the toxin in the paralysis observed in earthworms, and the authors indicate that further studies are needed to confirm the role of tetrodotoxin in predation by these worms. Tetrodotoxin may also be used as a defensive (anti-predatory) toxin in these flatworm species as seen in marine flatworms, blue-ringed octopus, and rough-skinned newts among others.
For reference:

shebebusynow a year ago

So interesting to see yet another small creature with tetrodotoxin (our local one is the rough skinned newt). This creature looks like a Hollywood invention--wouldn't be surprised to see something like it in horror movies. Wonder what the advantage is to having such a big head. Seems like it would make burrowing more difficult.

Christine Y.
Christine Y. a year ago

Lovely ;P

AlbertKang a year ago

Thanks, @Jamie Grant :)

Jamie Grant
Jamie Grant a year ago

Beautiful in a weird sort of way!

AlbertKang a year ago

Thanks for your appreciation, @Muckpuk and indeed, this one is slimy-ly pretty :D

Muckpuk a year ago

Kind of pretty!

Spotted by

Tawau, Sabah, Malaysia

Lat: 4.41, Long: 117.93

Spotted on Jan 26, 2018
Submitted on Feb 14, 2018

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