Sand Worm ID

[thaliaTLH]

Hello all!

I have done some independent research and was not able to come up with much. Can anyone help me ID this sand dwelling worm? He was discovered when I was turning the sand bed and he was removed. I will attach a video of him in the tank and a photo of him removed in the yellow cup. Thanks!

Thalia

 

[SnazzyUrchin792]

@ISpeakForTheSeas

 

[ChiCity]

my christ!

it looks like this…

hybridized with this

(… big shudders!)

 

[thaliaTLH]

my christ!

it looks like this…

hybridized with this

(… big shudders!)

Truly!!

 

[ISpeakForTheSeas]

Welcome to Reef2Reef!

@ISpeakForTheSeas

I'm actually a little frustrated with this one, as I know I've seen a worm like this with those kinds of bristles before, but I can't remember what kind it was.

OP, any chance you can get a pic of the worm against a black or white backdrop instead of the yellow?

I will say, the smooth-looking body and the way the worm moves in the video have me thinking it's likely predatory toward something - likely either worms, mollusks (snails, clams, etc.), and/or possibly pods. (Thankfully very few worms are harmful to the fish and ornamental inverts we keep).

 

[thaliaTLH]

Welcome to Reef2Reef!

I'm actually a little frustrated with this one, as I know I've seen a worm like this with those kinds of bristles before, but I can't remember what kind it was.

OP, any chance you can get a pic of the worm against a black or white backdrop instead of the yellow?

I will say, the smooth-looking body and the way the worm moves in the video have me thinking it's likely predatory toward something - likely either worms, mollusks (snails, clams, etc.), and/or possibly pods. (Thankfully very few worms are harmful to the fish and ornamental inverts we keep).

Thank you! Sure thing! I hope these are more clear. Thanks so much for helping! I have seen lots of fun worms in my tanks over the years, but nothing like this guy.

 

[ISpeakForTheSeas]

Thank you! Sure thing! I hope these are more clear. Thanks so much for helping! I have seen lots of fun worms in my tanks over the years, but nothing like this guy.

Yeah, these are better - this worm is from the taxonomic family Opheliidae, subfamily Ophelininae, probably either the genus Armandia or Ophelina.

Both of these genera are actually deposit feeders (so they literally eat the sand/dirt around them and digest the food mixed in with it), with Armandia species typically being smaller (a few centimeters) and preferring coarser sediments (sand and gravel) and Ophelina species being larger and preferring fine sediment (mud). They are both noted for moving with undulation, rather than the typical bristleworm movements.*

Anyway, these - surprisingly - should be harmless/beneficial clean up crew members; pretty neat!

*Source:
Diet of Worms Emended: An Update of Polychaete Feeding Guilds - Appendix A - Family-by-Family Review
(The paper)
https://www.annualreviews.org/content/journals/10.1146/annurev-marine-010814-020007 (The link you can download the Appendix from)

Diet of Worms Emended: An Update of Polychaete Feeding Guilds | Annual Reviews

Polychaetes are common in most marine habitats and dominate many infaunal communities. Functional guild classification based on taxonomic identity and morphology has linked community structure to ecological function. The functional guilds now include osmotrophic siboglinids as well as...

www.annualreviews.org

 

[thaliaTLH]

Thank you so much! This is super comprehensive! I will drop him back in!

 

[ISpeakForTheSeas]

Thank you so much! This is super comprehensive! I will drop him back in!

Happy to help!