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by Jean-Marie Cavanihac, France
When trying to feed them with Artemia nauplii, I noticed that they didn't react to the nauplii motions even when they were moving in front of the arrow worm's head. Artemia's swimming technique is very different to copepods and the arrow worms seem to be able to distinguish the Artemia nauplii movements from the copepod's distinctive movements, but not using their rudimentary eyes but using vertical rows of hairs all around their bodies.

The picture displays 'bubble-like' features within the thorax. Maybe they are eggs because some days later, I found several small chaetognaths in the water and these spherical features had disappeared.

As the story must have a fair ending, the arrow worm although a predator, is also eaten by little jellyfish!
Back to the first page Did you already see the details of the arrow worm?

All the pictures were taken of live specimens.

Comments to the author Comments to the author sent via our contacts page quoting page url plus : ('jcavanihac','')">Jean-Marie Cavanihac are welcomed.

All photographs Jean-Marie Cavanihac 1999

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Published in the January 2000 edition of Micscape Magazine.

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