Flatworm ID, Acoel or AEFW?

[rongy]

Hi reefers, wondering if anyone can help ID flatworm. Found them when dipping my new acro in quarantine system. I’ve been dipping them weekly for almost 2 months, and there are still some fell off after the dip. I think they’re acoel as their have swallowtail, but would like to confirm it.

 

[rongy]

Anyone?

 

[Troylee]

Looks like a aefw to me… I’ve never looked at one under a scope thou so I can’t say for sure.. any eggs on the frag? That’s a tell, tale sign.. or
Bite marks.

 

[ISpeakForTheSeas]

Anyone?

Ironically, these may be easier to identify without the microscope, but I'm thinking some sort of Acoel species because of the two points/tips by the tail.

 

[rongy]

Looks like a aefw to me… I’ve never looked at one under a scope thou so I can’t say for sure.. any eggs on the frag? That’s a tell, tale sign.. or
Bite marks.

I got those frags two months ago, and they’re heavily infected with AEFW. Bite marks, eggs in the base. I removed all the visible eggs, and placed them in quarantine system. I do weekly bayer dip for at least 8 consecutive weeks, but I still notice those small worms fell off. They’re like baby worms that I can barely see with my eye, never noticed anything adult size.

 

[rongy]

Ironically, these may be easier to identify without the microscope, but I'm thinking some sort of Acoel species because of the two points/tips by the tail.

They’re too small to see without microscope. The picture above is after 100x in microscope

They’re even smaller than the pods

 

[ISpeakForTheSeas]

They’re too small to see without microscope. The picture above is after 100x in microscope

They’re even smaller than the pods

Wow, those are tiny then.

I'm still thinking Acoel, but I'm not well-versed in the microscopic species yet (I only know one two that small at the moment).

For reference, here are some pics of AEFW for comparison (top link is larval pics, bottom is adult):

https://www.researchgate.net/figure/a-Live-and-b-fixed-pre-hatching-embryos-c-Phalloidin-staining-of-F-actin-reveals_fig4_225666939

https://www.researchgate.net/figure/Amakusaplana-acroporae-sp-nov-a-Live-adult-on-Acropora-sp-with-cluster-of-feeding_fig1_225666939

 

[rongy]

Wow, those are tiny then.

I'm still thinking Acoel, but I'm not well-versed in the microscopic species yet (I only know one two that small at the moment).

For reference, here are some pics of AEFW for comparison (top link is larval pics, bottom is adult):

https://www.researchgate.net/figure/a-Live-and-b-fixed-pre-hatching-embryos-c-Phalloidin-staining-of-F-actin-reveals_fig4_225666939

https://www.researchgate.net/figure/Amakusaplana-acroporae-sp-nov-a-Live-adult-on-Acropora-sp-with-cluster-of-feeding_fig1_225666939

Thanks for the info. Will definitely do some reading and comparisons. I’m also leaning toward acoel since they got two tips at the tail, but I definitely don’t want to risk it.