Worried about one of the babies

[Cryp_Sis]

Hi everyone,
I have noticed something a bit strange about one of the month-old bimaculoides hatchlings. He has an oddly-coloured section, that appears to be within his mantle (see attached photo). I am pretty certain it is internal, since it is sometimes nearly invisible, depending on what he’s doing with his mantle chromatophores (i.e. if he is darkly coloured it is not noticeable, but light colouring or translucency make it obvious. In most lights it appears greenish (not sure how well this will come out in the photo). Has anyone seen anything like this before? He is perfectly able to hunt, and eats what he catches (I have some video of him successfully hunting a live ghost shrimp this morning, which I might post elsewhere, the quality is not great). I have not seen him flash eyespots, as many of the others do, but otherwise no odd behaviour that I have noticed. I first noticed the green patch a few days ago, and I haven't seen it get worse.
I’m worried it’s some kind of nasty infection. I haven’t seen anything like it in any of the other 57 babies, and any advice or ideas would be very welcome.
Thanks so much!
Lene.

 

[L8 2 RISE]

WOW, 58 babies and you notice something wrong with a single one of them, now that's dedication! I can't say much for what it could be though. There's probably not much you can do for such a small little guy, my guess would be that if it's any parisite or infection, the treatment would also kill the octopus. I'm just guessing though. It does look like it's inside the body, but it might just be a coloration difference...

 

[DWhatley]

Lene,
I have not had a bimac and have only worked with a couple of infections with success only in the case of external problems using tetracycline in the food. The reason I am posting at all is to ask if the grey line on the left side is only in the photo or something you can see in the octopus' mantle. It looks somewhat similar to markings I saw on a female that did not survive more than a day (see photo and notes beginning at post 12). No one came up with anything regarding the markings but I suspect parasites and you may want to isolate the baby just in case.