Weird worm critter.

[Maebh]

Found this weird worm critter in my tank Not thrilled at all. Does anyone know what it is? Hasn't burrowed under the sand a few mins later. Kinda looks like it has legs?!

 

[EeyoreIsMySpiritAnimal]

Can you put it in a small container of tank water and take pics?

 

[WalkerLoves_TheOcean]

I agree with above, that would be very helpful since the worm blends in with the sand.

Try to take the picture with the container on a black background if possible.

 

[Maebh]

Thank you both! @WalkerLoves_TheOcean @EeyoreIsMySpiritAnimal

I should have taken it out cause now it's disappeared in my tank I'll keep an eye out for it. Someone said it looks like a fish parasite but I don't have any fish in the tank. I did take some seaweed from the ocean and put it in a few weeks ago, so maybe that's where it came from.

 

[Maebh]

Looking at other threads, I'm seeing similar worms identified as: baby bristle worm, Bobbitt worm, Dorvilleidae or a saltwater millipede. I feel one is worse than the others I don't think it's a Bobbitt though.
@ISpeakForTheSeas Do you think you could Id? sorry for calling on ya!

 

[ISpeakForTheSeas]

Looking at other threads, I'm seeing similar worms identified as: baby bristle worm, Bobbitt worm, Dorvilleidae or a saltwater millipede. I feel one is worse than the others I don't think it's a Bobbitt though.
@ISpeakForTheSeas Do you think you could Id? sorry for calling on ya!

Someone said it looks like a fish parasite but I don't have any fish in the tank.

Haha, I don't mind the tag - the video is a lot clearer than the pic.

The video shows it's a Polychaete (a bristleworm) of some variety with cephalic tentacles (tentacles on its head).

So, it's definitely not a parasite - no concerns there. Also, to my knowledge, saltwater millipedes don't exist - if someone says "saltwater millipede" it's a pretty safe assumption that they're actually talking about a bristleworm of some kind.

Anyway I can't tell how many tentacles your worm has on its head, but as a general rule, 5 tentacles = Eunicid worm (this category of worms includes predators like the Bobbit and others, but many of these are also harmless/beneficial CUC like most other bristleworms), 4 tentacles = Dorvilleid worm (harmless/beneficial), and a different number means a different kind of worm.

I'd guess yours is a Dorvilleid, but if you can count the tentacles that'd tell you for sure.

Also, just to clarify here, bristleworm is less a specific ID and more a category ID (referring to the taxonomic class Polychaeta). Calling something a bristleworm is like calling something a crab or a fish - it's generally helpful, but not specific. The other groupings like Eunicid and Dorvilleid are more specific, but even those are still category IDs rather than species IDs (taxonomic families Eunicidae and Dorvilleidae).

Fortunately, though, those family level IDs are usually good enough with worms (and ID's lower than that can get really difficult depending on the family with worms).

 

[Maebh]

Haha, I don't mind the tag - the video is a lot clearer than the pic.

The video shows it's a Polychaete (a bristleworm) of some variety with cephalic tentacles (tentacles on its head).

So, it's definitely not a parasite - no concerns there. Also, to my knowledge, saltwater millipedes don't exist - if someone says "saltwater millipede" it's a pretty safe assumption that they're actually talking about a bristleworm of some kind.

Anyway I can't tell how many tentacles your worm has on its head, but as a general rule, 5 tentacles = Eunicid worm (this category of worms includes predators like the Bobbit and others, but many of these are also harmless/beneficial CUC like most other bristleworms), 4 tentacles = Dorvilleid worm (harmless/beneficial), and a different number means a different kind of worm.

I'd guess yours is a Dorvilleid, but if you can count the tentacles that'd tell you for sure.

Also, just to clarify here, bristleworm is less a specific ID and more a category ID (referring to the taxonomic class Polychaeta). Calling something a bristleworm is like calling something a crab or a fish - it's generally helpful, but not specific. The other groupings like Eunicid and Dorvilleid are more specific, but even those are still category IDs rather than species IDs (taxonomic families Eunicidae and Dorvilleidae).

Fortunately, though, those family level IDs are usually good enough with worms (and ID's lower than that can get really difficult depending on the family with worms).

Thank you so much! Just to double check, would you say it is something to worry about? I'll keep an eye out and grab him if I see him. Thank you again!

 

[Devisissy]

Thank you both! @WalkerLoves_TheOcean @EeyoreIsMySpiritAnimal

I should have taken it out cause now it's disappeared in my tank I'll keep an eye out for it. Someone said it looks like a fish parasite but I don't have any fish in the tank. I did take some seaweed from the ocean and put it in a few weeks ago, so maybe that's where it came from.

Um, duh? LOL!

 

[ISpeakForTheSeas]

Just to double check, would you say it is something to worry about?

Probably not. It's most likely harmless/beneficial, but double checking the number of tentacles on the head wouldn't hurt.

 

[CKW]

Thank you so much! Just to double check, would you say it is something to worry about? I'll keep an eye out and grab him if I see him. Thank you again!

Get an arrow crab. They will take care of it for you.