Coral worm + arrow crab ID

[moretor1]

I saw this sand covered worm growing between gsp polyps, at first thought it was debris but then a second popped up and the first got larger.

After blowing on them with a pipette (I was trying to get rid of the algae) my purple dottyback (psuedochromis) came and ate both before I could get some better photos. Problem solved I guess...

As for the crab I'm certain it's either a frilly arrow crab (podochela sp) or a decorator arrow crab (Stenorphynchus sp.) But most photos of the decorator are much darker in color. If this is a decorator will it get darker as it ages like some crustaceans? I can see a very faint red spotted pattern on it

The crab itself is awesome. He will take the algae off his legs and strip the particles out of it with his claw and then put it back!!! I will try to get a video next time because it was cool as ****

 

[vetteguy53081]

I saw this sand covered worm growing between gsp polyps, at first thought it was debris but then a second popped up and the first got larger.

After blowing on them with a pipette (I was trying to get rid of the algae) my purple dottyback (psuedochromis) came and ate both before I could get some better photos. Problem solved I guess...

As for the crab I'm certain it's either a frilly arrow crab (podochela sp) or a decorator arrow crab (Stenorphynchus sp.) But most photos of the decorator are much darker in color. If this is a decorator will it get darker as it ages like some crustaceans? I can see a very faint red spotted pattern on it

The crab itself is awesome. He will take the algae off his legs and strip the particles out of it with his claw and then put it back!!! I will try to get a video next time because it was cool as ****

Pics are very dark to positively i.d. third pic looks like the crown of a sea cucumber but a guess based on lighting

 

[betareef]

Just replied in a similar thread. "Worm" could be same as this. I think it may be a brittle star, but haven't yet seen the body to be certain. Certainly moves like a brittle star.

 

[moretor1]

Just replied in a similar thread. "Worm" could be same as this. I think it may be a brittle star, but haven't yet seen the body to be certain. Certainly moves like a brittle star.

I should say it was 100% a worm because when the dottyback ate it the rest of its body hung out and hasn't moved since

 

[moretor1]

Pics are very dark to positively i.d. third pic looks like the crown of a sea cucumber but a guess based on lighting

Bad lighting. The crab was the focus of the last pic

 

[vetteguy53081]

I should say it was 100% a worm because when the dottyback ate it the rest of its body hung out and hasn't moved since

Agree on brittle star and a keeper. Eats uneaten food and detritus

 

[moretor1]

The picture isn't clear but I'm 99% sure the worms are sand mason worms. The tubes were made of sand and I could make out clear grains

 

[ISpeakForTheSeas]

The picture isn't clear but I'm 99% sure the worms are sand mason worms. The tubes were made of sand and I could make out clear grains

Lots of different worms build sand tubes like this - keep an eye out to see if the worm regrows (some worms - like Spionids - regularly get large chunks of their bodies eaten, and they just regrow it over the next like two weeks). If it has two tentacles that stick out of the tube, then it's either a Spionid or Chaetopterid.

Given the location of it on the coral, my concern would be that you might have a Coral-boring Spionid Worm species, which can cause major problems in a tank.

As for the crab I'm certain it's either a frilly arrow crab (podochela sp) or a decorator arrow crab (Stenorphynchus sp.)

Can you get a straight-on pic of the crab from the top showing the crab's full body, a second straight-on pic of just the head/antennae and such from the top, and a third straight-on pic of the crab and its claws from the front (all pics under white lighting)?

Those could help with determining exactly what kind of crab you have.

 

[moretor1]

Lots of different worms build sand tubes like this - keep an eye out to see if the worm regrows (some worms - like Spionids - regularly get large chunks of their bodies eaten, and they just regrow it over the next like two weeks). If it has two tentacles that stick out of the tube, then it's either a Spionid or Chaetopterid.

Given the location of it on the coral, my concern would be that you might have a Coral-boring Spionid Worm species, which can cause major problems in a tank.

Can you get a straight-on pic of the crab from the top showing the crab's full body, a second straight-on pic of just the head/antennae and such from the top, and a third straight-on pic of the crab and its claws from the front (all pics under white lighting)?

Those could help with determining exactly what kind of crab you have.

Lots of different worms build sand tubes like this - keep an eye out to see if the worm regrows (some worms - like Spionids - regularly get large chunks of their bodies eaten, and they just regrow it over the next like two weeks). If it has two tentacles that stick out of the tube, then it's either a Spionid or Chaetopterid.

Given the location of it on the coral, my concern would be that you might have a Coral-boring Spionid Worm species, which can cause major problems in a tank.

Can you get a straight-on pic of the crab from the top showing the crab's full body, a second straight-on pic of just the head/antennae and such from the top, and a third straight-on pic of the crab and its claws from the front (all pics under white lighting)?

Those could help with determining exactly what kind of crab you have.

The worm itself never poked put when I was watching. They may have been killed by a dip a while ago

When it was eaten, whatever was left hanging out was pinkish and hasn't moved since

These are the best photos of the crab I could get so far. He doesn't like to sit still

 

[ISpeakForTheSeas]

Ironically, those pics are actually slightly too bright (they've got a glare/reflection from the bright light) - right idea though. Again, aerial-esque pics (i.e. pics taken from above the crab looking down on it) would be the most helpful.

That said, it's definitely not a Stenorhynchus species. It might be a Podochela species, but I can't tell for sure from the pics.