Multi Legged Pink WORM

[troi]

I have found many of these worms living in the substrate or under the driftwood in several of my tanks. They appear to be freshwater Polychaeta, from under an inch to about four inches. When they swim, they wiggle their paired legs and make an "S" motion in the water. I think they came in on the roots of plants from a certain LFS.

Anyone else get them in tanks? What are they? are they harmless, neutral, beneficial? How big do they get? I kinda like them and keep a few in a seperate container with water and sand.

I havent' been able to locate them on the internet. Ask if you need a more detailed description for ID.

troi

[Mike_Noren]

While it is possible they're polychaetes, it's more likely they're naidids or close ally of naidids. Naidids are a type of water-living earthworm adapted to a more active life than, say, Tubifex. A typical naidid looks something like this: http://www.wigry.win.pl/wodne/pionowe/69.gif
http://www.micrographia.com/specbiol/he ... ylar00.jpg

Both pictures are of a member of the same very common genus, Stylaria.

Whether oligochaetes or polychaetes, they're highly unlikely to be detrimental to your fish.

[troi]

While it is possible they're polychaetes, it's more likely they're naidids or close ally of naidids. Naidids are a type of water-living earthworm adapted to a more active life than, say, Tubifex. A typical naidid looks something like this: http://www.wigry.win.pl/wodne/pionowe/69.gif
http://www.micrographia.com/specbiol/he ... ylar00.jpg

Definitely not my worm but similar: My worms have paired legs at each joint or segment (can't quite tell which)where the one in the photo has wispy, bristle like things. they have paired eyes, what looks like a central blood vessel, a "gut" where I can see changes in color as what I assume is food moves thru. There is no pointy appendage at the end of the critter. The legs appear to be sorta hard and unjointed, maybe chitanous?, on a nake eye inspection. I may be able to see a mouth, but I might be making up that part from memory. Similar enough to the photo to be closely related, I think.

Closest thing I saw in a web search was marine bristle worms. My worms don't have a cluster of bristles, tho, just the "legs."

Thnaks for the links, tho. Someone on a goldfish list suggested strylaria; it is good to see what one looks like.
I don't think my camera is up to a decent close up.

troi

[Mike_Noren]

Definitely not my worm but similar: My worms have paired legs at each joint or segment --- they have paired eyes, what looks like a central blood vessel, ---
Closest thing I saw in a web search was marine bristle worms. My worms don't have a cluster of bristles, tho, just the "legs."

Yes, you have just described a polychaete. Congrats, I've never even seen a freshwater polychaete.

It's a shame you're not in Sweden, I would have liked to obtain a few.

[troi]

Yes, you have just described a polychaete. Congrats, I've never even seen a freshwater polychaete.

It's a shame you're not in Sweden, I would have liked to obtain a few.

I will try to look closer with a glass or the 'scope and see if there really is a pointy tail. I lucked out on this semi-ID: "worm" was easy, segmented with rudimentry systems rang a bell as annalid from high school or college bio classes, so that's where I started. But no freshwater polychaets anywhere. Asked local scientists at a convention on the delta etc.

They could come from anywhere--the shop they come in from gets plants from places no one else seems to.

I did find one biology student--aquarist who said he had heard of some but he had no other info.

These I keep and feed are not getting loose in my tanks till I find out for sure how they interact with fish.

I may be able to get more or get these guys breeding, which they like to do in the substrate. Is it possible to just send wet things to Sweden in an envelope, they are pretty hardy? I can go raid the shop's plant tank substrate...

troi