Flatworm id please

reeferab

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I spotted this on a new frogspawn (green one in the front) I added. It was on the tentacles and visible when the flow was off.

I did dip in coral x but not for very long and enough concentration probably. I did notice a worm in the bag (see photo - not the same as one under the scope).

The photo is under a microscope with a 4x objective and 10x eyepiece for 40x magnification.

Worm was damaged when extracting and placing on the slide. It was readily attaching to various surfaces inc the pipette. Both segments of the worm were moving / sliding on the slide.

Wondering (hoping?) it’s not a euphylia eating flatworm.

Any help greatly appreciated! 🙏


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EnterName

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As your flatworm was damaged it is hard to estimate its shape.
Here is an image of what I assume to be juvenile "ghost flatworm" from my microscopy thread (ignore the hole in its center):
Flatworm1.jpg
These guys spread relatively fast but don't seem to bother corals.
This is how they look like with the naked eye:
PXL_20251123_123546838~2.jpg

If yours look similar, you are most likely fine.
You can find images of other flatworms in the Hitchhiker Guide thread.
 

EnterName

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Flatworms are quite squishy so they change their shape quite significantly while moving around and especially if they are getting damaged during transfer onto the microscope slide.

I think we need a decent image of an undamaged individual before a proper identification is possible.

EEFW can have split tails as well: https://www.bareefers.org/forum/attachments/476cf39a-36a5-4556-86c3-8d8fbbded4e9-jpeg.46923/

And in many cases they also seem to get really large: https://reefbuilders.com/wp-content/blogs.dir/1/files/2020/08/euphyllia-flatworm-large.jpg

There will be multiple genera or at least species that eat euphyllia, and sometimes harmless flatworms climb onto corals as well. If these guys seem to concentrate on the euphyllia and don't sit on the glass or rocks, etc. then I would start to worry.
 
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reeferab

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As your flatworm was damaged it is hard to estimate its shape.
Here is an image of what I assume to be juvenile "ghost flatworm" from my microscopy thread (ignore the hole in its center):
Flatworm1.jpg
These guys spread relatively fast but don't seem to bother corals.
This is how they look like with the naked eye:
PXL_20251123_123546838~2.jpg

If yours look similar, you are most likely fine.
You can find images of other flatworms in the Hitchhiker Guide thread.
Thanks very much - good to have the images. Definitely a more of an oval shape and no double tail. So looks like more like EEFW :(
 

EnterName

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As your flatworm was damaged it is hard to estimate its shape.
Here is an image of what I assume to be juvenile "ghost flatworm" from my microscopy thread (ignore the hole in its center):
Flatworm1.jpg
These guys spread relatively fast but don't seem to bother corals.
This is how they look like with the naked eye:
PXL_20251123_123546838~2.jpg

If yours look similar, you are most likely fine.
You can find images of other flatworms in the Hitchhiker Guide thread.
Thanks very much - good to have the images. Definitely a more of an oval shape and no double tail. So looks like more like EEFW :(
That's unfortunate...

A coral dip will get rid of some of them, but I don't think eggs will be affected and as soon as the next generation hatches you will face the same issue. Repeatedly dipping may stress the coral too much and I assume there is no way around some form of treatment if these flatworms are actually causing trouble.

I'm not very experienced with flatworm treatment so maybe someone else will be able to help with finding a solution or suitable product.

Good luck!
 

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