What this weird little worm

JacobNeighbors

New Member
View Badges
Joined
Aug 10, 2026
Messages
4
Reaction score
2
Rating - 0%
0   0   0
20260810_101857_A53BEE66-8A5A-4358-B001-1CC12E815D2F.png


20260810_101858_C6630DE5-697B-4F3C-A6FA-E79CA719DAA2.png


20260810_101858_2F8507DC-BFD5-46E0-AA8B-CF98307284FB.png

I just found this little banded worm/tentacle in my live rock. It doesn’t look like any polychaete or spionid to me.

Here are some pictures and vid of it. Can someone help me id it?
 
Peanut worm. The video shows how it basically "folds out of itself" you can see its "introvert" (anterior section) coming out of itself like you can push the toe of a sock into the heel until the whole thing turns inside-out and disappears into a lump.

https://melevsreef.com/blogs/peanut-worm-pictures

Not a definite ID but showing how there are peanut worms with this color/pattern:
https://reeflex.net/tiere/12161_Phascolosoma_Phascolosoma_agassizii.htm
https://reeflex.net/tiere/7968_Sipunculus_sp.htm
https://reeflex.net/tiere/1643_Phascolosoma_cf_nigrescens.htm
 
Last edited:
Peanut worm. The video shows how it basically "folds out of itself" you can see its "introvert" (anterior section) coming out of itself like you can push the toe of a sock into the heel until the whole thing turns inside-out and disappears into a lump.

https://melevsreef.com/blogs/peanut-worm-pictures

Not a definite ID but showing how there are peanut worms with this color/pattern:
https://reeflex.net/tiere/12161_Phascolosoma_Phascolosoma_agassizii.htm
https://reeflex.net/tiere/7968_Sipunculus_sp.htm
https://reeflex.net/tiere/1643_Phascolosoma_cf_nigrescens.htm
Thank you very much! I think it is a peanut worm considering its pattern and mouth opening structure. It is a reef safe creature?
 
Peanut worm. The video shows how it basically "folds out of itself" you can see its "introvert" (anterior section) coming out of itself like you can push the toe of a sock into the heel until the whole thing turns inside-out and disappears into a lump.

https://melevsreef.com/blogs/peanut-worm-pictures

Not a definite ID but showing how there are peanut worms with this color/pattern:
https://reeflex.net/tiere/12161_Phascolosoma_Phascolosoma_agassizii.htm
https://reeflex.net/tiere/7968_Sipunculus_sp.htm
https://reeflex.net/tiere/1643_Phascolosoma_cf_nigrescens.htm
Thank you very much! I think it is a peanut worm considering its pattern and mouth opening structure. It is a reef safe creature?
Peanut worms are generally considered reef safe.

Some peanut worms have a weird symbiotic relationship with corals that make them look like parasites by drilling into coral tissue. But apparently its actually beneficial. It's a very rare sight though.

I've not seen a dangerous peanut worm yet, you should be fine 🙂
 
Peanut worm. The video shows how it basically "folds out of itself" you can see its "introvert" (anterior section) coming out of itself like you can push the toe of a sock into the heel until the whole thing turns inside-out and disappears into a lump.

https://melevsreef.com/blogs/peanut-worm-pictures

Not a definite ID but showing how there are peanut worms with this color/pattern:
https://reeflex.net/tiere/12161_Phascolosoma_Phascolosoma_agassizii.htm
https://reeflex.net/tiere/7968_Sipunculus_sp.htm
https://reeflex.net/tiere/1643_Phascolosoma_cf_nigrescens.htm
Thank you very much! I think it is a peanut worm considering its pattern and mouth opening structure. It is a reef safe creature?
Peanut worms are generally considered reef safe.

Some peanut worms have a weird symbiotic relationship with corals that make them look like parasites by drilling into coral tissue. But apparently its actually beneficial. It's a very rare sight though.

I've not seen a dangerous peanut worm yet, you should be fine 🙂
Thank you very much for the information! I’ll keep an eye out for it. It’s pretty cute.
 

TOP 10 Trending Threads

WHICH AREA OF REEFKEEPING MOST NEEDS A GENUINE BREAKTHROUGH?

  • Lighting

    Votes: 1 2.8%
  • Pumps and water flow

    Votes: 1 2.8%
  • Water testing and monitoring

    Votes: 12 33.3%
  • Controllers, apps, and device compatibility

    Votes: 5 13.9%
  • Filtration and nutrient export

    Votes: 1 2.8%
  • Automatic feeding

    Votes: 4 11.1%
  • Leak prevention and tank safety

    Votes: 5 13.9%
  • Equipment reliability and repairability

    Votes: 4 11.1%
  • Other (leave a comment in the thread)

    Votes: 3 8.3%
Back
Top
Home
Post thread…
Market
What's new