Weird Egg with flagellum? Polyp? Coral or crab eggs?

BloopFish · Jan 6, 2020

eschaton said:
Someone else had something similar recently, but was also unable to identify them.

To me they look like tunicate larvae, but they seem way too large to be that.

You might be onto something, even though you do say they look too large to be it they really do look like tunicate larvae... but why was it so gathered around the sponge crab? Sponge crabs are known to also carry Ascidians when sponge is not present, but none came with the sponge crab.

eschaton · Jan 6, 2020

BloopFish said:
You might be onto something, even though you do say they look too large to be it they really do look like tunicate larvae... but why was it so gathered around the sponge crab? Sponge crabs are known to also carry Ascidians when sponge is not present, but none came with the sponge crab.

All the pictures I can find of tunicate larvae online are taken under microscope. I am not sure if they have macroscopic larvae such as is shown in the original picture.

BloopFish · Jan 6, 2020

eschaton said:
All the pictures I can find of tunicate larvae online are taken under microscope. I am not sure if they have macroscopic larvae such as is shown in the original picture.

I can't seem to find any information on the size of tunicate larvae either - the size of the ones I observed was around the size of a brine shrimp egg - maybe slightly smaller. The unidentified purple thing looks more like a vertebrate than an invertebrate, and I currently house no fish, so it does seem like a very convincing guess.

HotManwich · Jan 7, 2020

Are you able to put it in ethanol? 70% is the standard for preservation at the museum I work at, 95% if genetics is going to be done on it. If you're able to put it in a small glass vial with some ethanol it should last and not fall apart so that you can at least save it for future reference or someone wants to take a better look!

BloopFish · Jan 7, 2020

HotManwich said:
Are you able to put it in ethanol? 70% is the standard for preservation at the museum I work at, 95% if genetics is going to be done on it. If you're able to put it in a small glass vial with some ethanol it should last and not fall apart so that you can at least save it for future reference or someone wants to take a better look!

I was thinking about this and thought it would be too late to do this but... another mass of the purple "eggs" has occurred in the same area while doing a water change. I thoroughly checked and the sponge crab isn't berried - not like it looks like crab eggs anyways. I preserved three of the unidentified creatures in 70% alcohol. Felt a little cruel killing the unusual creature. The picture here is of the purple things gathered in the corner of the acclimation chamber. The acclimation chamber has some fresh dry rock, chaeto, sponge crab, and shame faced crabs.