Anybody seen these bristle-footed cuties?

[bearceea]

Hi all,

I operate a small chilled (18C) marine tank in a research lab, to host wild-caught Pacific (southern Cali coastal) sea squirts for cell and developmental biology purposes. I've been enjoying fostering all of our miscellaneous hitchhikers with occasional brine shrimp feedings. (We generally have small brittle stars, lots of gammarid amphipods, some small orange worms, and of course, the ever present Aiptasia-- but our sea squirts don't actually need to feed for the short duration that they inhabit my tank & we don't have any fish... so when the anemones start proliferating too much I just starve them out by stopping all brine shrimp feedings.) Recently, after I had the lights off for several days to starve out my algae growth, a bristle-footed worm meandered out, approximately 2 inches. She quickly scuttled back into the sand under some tank decor, once the lights came back on. I've named her Princess. I know chilled tanks are mostly uncharted territory, but does anyone have an ID?

 

[Rocks reef]

I'm curious but I can't see the pics...

 

[BonnieB]

That looks like a bristle worm in the screenshot but the video doesn’t play. Upload it to YouTube then repost it so we’re can be sure to help you out.

 

[exnisstech]

@ISpeakForTheSeas ?

 

[bearceea]

Hi all! Sorry, not sure why the video isn't playing here, I thought Imgur worked for depositing. The video is uploaded to Youtube now, and available here!

 

[BonnieB]

Princess definitely looks like a bristle worm in the video, but when I was doing some research it isn’t usually found in cold waters…although Chesapeake Bay’s (MD) Aquarium has them from their cold waters. I think @ISpeakForTheSeas would be the one who could definitively answer this for you.

 

[bearceea]

Princess definitely looks like a bristle worm in the video, but when I was doing some research it isn’t usually found in cold waters…although Chesapeake Bay’s (MD) Aquarium has them from their cold waters. I think @ISpeakForTheSeas would be the one who could definitively answer this for you.

Thanks! I am pretty sure several varieties of Bristleworms do show up in cool water pacific samplings too, so that indeed was my first thought. But she's not as clearly armored/segmented as some, & the coloring is quite different (burnished gold, nice markings on the tail), so I wondered if my initial "bristle feet = bristleworm" guess was leaving out other possibilities. Good to know there are more votes for "some kind of bristleworm." Thank you! :)

 

[twentyleagues]

That doesnt look like any common bristle worm to me. Does it have bristles? Is it some sort of worm? I'm gonna say yes to both but that is where the similarity ends for me.

 

[bearceea]

That doesnt look like any common bristle worm to me. Does it have bristles? Is it some sort of worm? I'm gonna say yes to both but that is where the similarity ends for me.

Thanks, I agree-- most bristle worms have pretty clear segmentation patterns, where she has a less 'plated' body (more caterpillar-like). But I don't know of that many other classes with bristle feet, so I'm kinda spitballing!

 

[twentyleagues]

Thanks, I agree-- most bristle worms have pretty clear segmentation patterns, where she has a less 'plated' body (more caterpillar-like). But I don't know of that many other classes with bristle feet, so I'm kinda spitballing!

I dont know if @ISpeakForTheSeas is all that active right now, I really hope they see this and take a look though. They have a lot of knowledge on stuff like this.

 

[ISpeakForTheSeas]

Hi all,

I operate a small chilled (18C) marine tank in a research lab, to host wild-caught Pacific (southern Cali coastal) sea squirts for cell and developmental biology purposes. I've been enjoying fostering all of our miscellaneous hitchhikers with occasional brine shrimp feedings. (We generally have small brittle stars, lots of gammarid amphipods, some small orange worms, and of course, the ever present Aiptasia-- but our sea squirts don't actually need to feed for the short duration that they inhabit my tank & we don't have any fish... so when the anemones start proliferating too much I just starve them out by stopping all brine shrimp feedings.) Recently, after I had the lights off for several days to starve out my algae growth, a bristle-footed worm meandered out, approximately 2 inches. She quickly scuttled back into the sand under some tank decor, once the lights came back on. I've named her Princess. I know chilled tanks are mostly uncharted territory, but does anyone have an ID?

@ISpeakForTheSeas ?

Princess definitely looks like a bristle worm in the video, but when I was doing some research it isn’t usually found in cold waters…although Chesapeake Bay’s (MD) Aquarium has them from their cold waters. I think @ISpeakForTheSeas would be the one who could definitively answer this for you.

I dont know if @ISpeakForTheSeas is all that active right now, I really hope they see this and take a look though. They have a lot of knowledge on stuff like this.

Yeah, I definitely don't have as much time to be active as I would like these days (my free-time is currently ridiculously limited), but I try to chime in when I can.

Welcome to Reef2Reef bearceea!

You've got a kind of Polychaete (Bristle Worm) known as a Scale Worm there (family Polynoidae), and I'd be at least a little surprised if it's not from the Polynoinae subfamily. However, scale worms aren't terribly common in the hobby, so I'm not terribly familiar with them and don't know for certain how to narrow down the ID from the family level just yet, so I may be off on that assumption. That said, I do know that figuring out exactly which species of scale worm you have can be tough due to the sheer number of genera/species in the family - especially without some very clear pics/thorough examination - but if you've got access to the worm, you can count the elytra (the paired "scales" of the scale worm on it's dorsal side; they're tough to see on your specimen, but based on the body pattern I believe I see at least fourteen pairs in the video) and the number of body segments it has (if you can get a clear, still photo of it, you can count the number of bristles (chaetae)/parapodia to help with that), and that can help you to eliminate some species at least.

Based on the few genera I am familiar with currently, though, (and assuming it is indeed from the Polynoinae subfamily), Harmothoe is the only one I remember at the moment that would be found in So Cal's waters with a similar look to this (black dots that are either part of the pattern visible on the elytra or a pair of visible eyes on the head - eyes are only sometimes visible on these; at least sometimes seen with an easily visibly reduced "tail;" no large/projecting, bulbous prostomium, etc.), so a species like H. imbricata (which is known to come in wide variety of colors/patterns but always with 15 pairs of elytra and fewer than 50 segments) may or may not be a decent place to start a search for a proper ID.

If nothing else, knowing that it's a scale worm, you may be able to reach out to a proper polychaete specialist and get a genus/species level ID.

Until you can get a proper ID, however, if you are wanting to feed it, it's most likely a generalist predator that primarily feeds on a wide variety of invertebrates (sponges, hydroids, foraminiferans, shrimp, amphipods, bivalves, etc.). It may also, however, feed on things like diatoms as well. So, I wouldn't expect it to be too difficult to feed, but I may be wrong. Personally, I'd try seeing if it would scavenge for a decent quality fish food and some krill or similar.

Anyway, that's the best ID I can offer at the moment - hope it helps!

 

[twentyleagues]

Yeah, I definitely don't have as much time to be active as I would like these days (my free-time is currently ridiculously limited), but I try to chime in when I can.

Welcome to Reef2Reef bearceea!

You've got a kind of Polychaete (Bristle Worm) known as a Scale Worm there (family Polynoidae), and I'd be at least a little surprised if it's not from the Polynoinae subfamily. However, scale worms aren't terribly common in the hobby, so I'm not terribly familiar with them and don't know for certain how to narrow down the ID from the family level just yet, so I may be off on that assumption. That said, I do know that figuring out exactly which species of scale worm you have can be tough due to the sheer number of genera/species in the family - especially without some very clear pics/thorough examination - but if you've got access to the worm, you can count the elytra (the paired "scales" of the scale worm on it's dorsal side; they're tough to see on your specimen, but based on the body pattern I believe I see at least fourteen pairs in the video) and the number of body segments it has (if you can get a clear, still photo of it, you can count the number of bristles (chaetae)/parapodia to help with that), and that can help you to eliminate some species at least.

Based on the few genera I am familiar with currently, though, (and assuming it is indeed from the Polynoinae subfamily), Harmothoe is the only one I remember at the moment that would be found in So Cal's waters with a similar look to this (black dots that are either part of the pattern visible on the elytra or a pair of visible eyes on the head - eyes are only sometimes visible on these; at least sometimes seen with an easily visibly reduced "tail;" no large/projecting, bulbous prostomium, etc.), so a species like H. imbricata (which is known to come in wide variety of colors/patterns but always with 15 pairs of elytra and fewer than 50 segments) may or may not be a decent place to start a search for a proper ID.

If nothing else, knowing that it's a scale worm, you may be able to reach out to a proper polychaete specialist and get a genus/species level ID.

Until you can get a proper ID, however, if you are wanting to feed it, it's most likely a generalist predator that primarily feeds on a wide variety of invertebrates (sponges, hydroids, foraminiferans, shrimp, amphipods, bivalves, etc.). It may also, however, feed on things like diatoms as well. So, I wouldn't expect it to be too difficult to feed, but I may be wrong. Personally, I'd try seeing if it would scavenge for a decent quality fish food and some krill or similar.

Anyway, that's the best ID I can offer at the moment - hope it helps!

Thank you!

 

[bearceea]

Yeah, I definitely don't have as much time to be active as I would like these days (my free-time is currently ridiculously limited), but I try to chime in when I can.

Welcome to Reef2Reef bearceea!

You've got a kind of Polychaete (Bristle Worm) known as a Scale Worm there (family Polynoidae), and I'd be at least a little surprised if it's not from the Polynoinae subfamily. However, scale worms aren't terribly common in the hobby, so I'm not terribly familiar with them and don't know for certain how to narrow down the ID from the family level just yet, so I may be off on that assumption. That said, I do know that figuring out exactly which species of scale worm you have can be tough due to the sheer number of genera/species in the family - especially without some very clear pics/thorough examination - but if you've got access to the worm, you can count the elytra (the paired "scales" of the scale worm on it's dorsal side; they're tough to see on your specimen, but based on the body pattern I believe I see at least fourteen pairs in the video) and the number of body segments it has (if you can get a clear, still photo of it, you can count the number of bristles (chaetae)/parapodia to help with that), and that can help you to eliminate some species at least.

Based on the few genera I am familiar with currently, though, (and assuming it is indeed from the Polynoinae subfamily), Harmothoe is the only one I remember at the moment that would be found in So Cal's waters with a similar look to this (black dots that are either part of the pattern visible on the elytra or a pair of visible eyes on the head - eyes are only sometimes visible on these; at least sometimes seen with an easily visibly reduced "tail;" no large/projecting, bulbous prostomium, etc.), so a species like H. imbricata (which is known to come in wide variety of colors/patterns but always with 15 pairs of elytra and fewer than 50 segments) may or may not be a decent place to start a search for a proper ID.

If nothing else, knowing that it's a scale worm, you may be able to reach out to a proper polychaete specialist and get a genus/species level ID.

Until you can get a proper ID, however, if you are wanting to feed it, it's most likely a generalist predator that primarily feeds on a wide variety of invertebrates (sponges, hydroids, foraminiferans, shrimp, amphipods, bivalves, etc.). It may also, however, feed on things like diatoms as well. So, I wouldn't expect it to be too difficult to feed, but I may be wrong. Personally, I'd try seeing if it would scavenge for a decent quality fish food and some krill or similar.

Anyway, that's the best ID I can offer at the moment - hope it helps!

Fantastic, thank you for the warm welcome to the channels and the family ID! I really appreciate that you took some time to pop in & share some knowledge.

Looks like you're very likely right about Polynoinae, lots of those images seem quite close. I look forward to reading more about Scale Worms. I've got the lights off again this weekend, so I'll drop some pellets & hopefully "she" will wander out so I can count segments. She has been very shy. (The tank is also filthy, so getting my glass clean enough for pictures would be a big help, but hopefully that means she's happy with the ehm, thriving ecosystem in there... hard to find cold water cleanup crew, other than falsely-advertised-as-tropical Margarita snails!) Seems like their reproductive cycles are broadly a bit hand-wavey, so I'll just keep my fingers crossed that she can pull off babies somehow. She's so cute, wouldn't want her to be all alone in there.