Walking dendros... what can you tell me about them?

[Reefkeepers Archive]

I was just checking a wholesaler website and noticed that they got walking dendro in stock, did alittle research and found them interesting, my LFS sources coral from this particular supplier so thought I'd order it through them. Though before I do, does anyone know anything about them? First time hearing about walking dendro, I know my fair share about NPS species, though not ones like this, my tank is moderately lit and there are definitely more shady spots, I already feed my tank every night (and somehow my phosphates are still zero) so thats not a problem, though I do have other sandbed corals. Any Care tips/instructions? Thanks!

 

[encrustingacro]

Walking dendros (Heteropsammia cochlea) are in the family Dendrophylliidae, a family made of mostly azooxanthelate genera. However, Heteropsammia are facultatively zooxanthellate, meaning they can live both with and without symbiotic algae. Generally, facultatively zooxanthellate corals will be zooxanthellate at shallower depths/tropical localities and will be azooxanthellate at aphotic depths/temperate localities.

 

[Reefkeepers Archive]

Walking dendros (Heteropsammia cochlea) are in the family Dendrophylliidae, a family made of mostly azooxanthelate genera. However, Heteropsammia are facultatively zooxanthellate, meaning they can live both with and without symbiotic algae. Generally, facultatively zooxanthellate corals will be zooxanthellate at shallower depths/tropical localities and will be azooxanthellate at aphotic depths/temperate localities.

Are they aggressive in nature? Also will they grow new polyps or stay singe polyped like a trachy?

 

[encrustingacro]

Are they aggressive in nature? Also will they grow new polyps or stay singe polyped like a trachy?

From what I know, Heteropsammia (along with most other dendrophylliids) are not aggressive, as they do not have sweeper tentacles; I could be wrong, though. They have a worm living inside them that moves them around, which could lead to them stinging/being stung by other corals.
As for whether Heteropsammia can grow new polyps, I have seen polystomatous Heteropsammia (or could have been Heterocyathus), although you it wouldn't split and form a new colony like an anemone.

 

[Reefkeepers Archive]

From what I know, Heteropsammia (along with most other dendrophylliids) are not aggressive, as they do not have sweeper tentacles; I could be wrong, though. They have a worm living inside them that moves them around, which could lead to them stinging/being stung by other corals.
As for whether Heteropsammia can grow new polyps, I have seen polystomatous Heteropsammia (or could have been Heterocyathus), although you it wouldn't split and form a new colony like an anemone.

Interesting, just wanted to make sure I wouldn't have to block off other coral if I add this, I was wondering if it had polyps like a lobo, as in multiple heads on one worm, not like a mushroom.

 

[encrustingacro]

Interesting, just wanted to make sure I wouldn't have to block off other coral if I add this, I was wondering if it had polyps like a lobo, as in multiple heads on one worm, not like a mushroom.

This is what I mean by "polystomatous;" they are on one base, but they have multiple mouths/corallites.
New Caledonia (Credit: Damien Brouste)

Lembeh Strait (Credit: Sylvain Le Bris)

 

[Reefkeepers Archive]

This is what I mean by "polystomatous;" they are on one base, but they have multiple mouths/corallites.
New Caledonia (Credit: Damien Brouste)

Lembeh Strait (Credit: Sylvain Le Bris)

Yup! That's exactly what I was wondering.

Also unrelated question, just noticed the trachy I picked up already had sweepers/filaments out, moved it far away from my lobo, though how will I/when will i know if there is any damage done or if he didn't get stung. Also are the thin, stringy filaments from the side of the coral mesenterial filaments? Also how much damage do they do?

 

[encrustingacro]

Yup! That's exactly what I was wondering.

Also unrelated question, just noticed the trachy I picked up already had sweepers/filaments out, moved it far away from my lobo, though how will I/when will i know if there is any damage done or if he didn't get stung. Also are the thin, stringy filaments from the side of the coral mesenterial filaments? Also how much damage do they do?

Can you post pics? The stringy filaments on the side are most likely mesenterial filaments. Generally, you would know if your coral was stung by mesenterial filaments, as portions that were stung would look damaged or have missing flesh.

 

[Reefkeepers Archive]

Can you post pics? The stringy filaments on the side are most likely mesenterial filaments. Generally, you would know if your coral was stung by mesenterial filaments, as portions that were stung would look damaged or have missing flesh.

Would it be immediate irritation or would it be more like a water parameter shift as it takes a few days to notice the damage? Also I can't get a photo as they are incredibly thin and the tank lights are out

 

[Reefkeepers Archive]

Can you post pics? The stringy filaments on the side are most likely mesenterial filaments. Generally, you would know if your coral was stung by mesenterial filaments, as portions that were stung would look damaged or have missing flesh.

I (thankfully) don't think It got stung as it's feeding arms are out, though i definitely won't underestimate that trachy, that coral is aggressive! Thanks for all the help!

 

[vetteguy53081]

These coral have inner worms that provide the movement hence the term WALKING and feed best in low light.

 

[OrchidMiss]

I'd like to know what @ISpeakForTheSeas says, too.
I've been very interested in dendros (walking or not) for a specific area in one of my tanks.

 

[encrustingacro]

Would it be immediate irritation or would it be more like a water parameter shift as it takes a few days to notice the damage? Also I can't get a photo as they are incredibly thin and the tank lights are out

Generally, it would be immediate irritation.

 

[ISpeakForTheSeas]

I'd like to know what @ISpeakForTheSeas says, too.
I've been very interested in dendros (walking or not) for a specific area in one of my tanks.

I don't have a whole lot to add, but I'll add what I can.

Heteropsammia cochlea is found in loose substrate (fine/sandy to coarse/gravelly) generally in relatively depths down to about 40 meters (with 8-20 meters being more typical, though they're not terribly uncommon down in the 30-40 meters range). As mentioned, they have a symbiotic relationship with the Sipunculan (peanut worm), Apsidosiphon (Aspidosiphon) muelleri, and with a cryptoendolithic (it hides inside the stony skeleton of the coral with the peanut worm) bivalve species, Jousseaumia sp. (A.K.A. Jousseaumiella sp.). I would assume Jousseaumia heteropsammiae, but I don't know for certain.

H. cochlea is thought (with good reason, since they can be found at 100 meters deep) to be facultatively photosynthetic (as was also mentioned above). They can receive adequate lighting even down at 40 meters deep, and they receive a fair amount of their photosynthesis from light reflected off the substrate beneath them into their skeleton on their underside. They can eat a relatively wide range of specimens, including salps (planktonic tunicates) and sacoglossan slugs (such as Elysia spp. lettuce slugs); they prefer foods that are less than 12mm in diameter, but they can eat (gelatinous) things as large as 50mm despite their gape only reaching 35mm. I would assume but can't confirm that they would eat more standard zooplankton (like copepods) as well.

That's all I've really been able to find on these guys so far.

 

[Reefkeepers Archive]

I don't have a whole lot to add, but I'll add what I can.

Heteropsammia cochlea is found in loose substrate (fine/sandy to coarse/gravelly) generally in relatively depths down to about 40 meters (with 8-20 meters being more typical, though they're not terribly uncommon down in the 30-40 meters range). As mentioned, they have a symbiotic relationship with the Sipunculan (peanut worm), Apsidosiphon (Aspidosiphon) muelleri, and with a cryptoendolithic (it hides inside the stony skeleton of the coral with the peanut worm) bivalve species, Jousseaumia sp. (A.K.A. Jousseaumiella sp.). I would assume Jousseaumia heteropsammiae, but I don't know for certain.

H. cochlea is thought (with good reason, since they can be found at 100 meters deep) to be facultatively photosynthetic (as was also mentioned above). They can receive adequate lighting even down at 40 meters deep, and they receive a fair amount of their photosynthesis from light reflected off the substrate beneath them into their skeleton on their underside. They can eat a relatively wide range of specimens, including salps (planktonic tunicates) and sacoglossan slugs (such as Elysia spp. lettuce slugs); they prefer foods that are less than 12mm in diameter, but they can eat (gelatinous) things as large as 50mm despite their gape only reaching 35mm. I would assume but can't confirm that they would eat more standard zooplankton (like copepods) as well.

That's all I've really been able to find on these guys so far.

Thanks! By any chance do you know if they are ah aggressive coral? Can they "walk" over rockwork? Also are they just a single polyp or can they grow more polyps like your classic dendrophyllia or sun coral?

 

[ISpeakForTheSeas]

Thanks! By any chance do you know if they are ah aggressive coral? Can they "walk" over rockwork? Also are they just a single polyp or can they grow more polyps like your classic dendrophyllia or sun coral?

I’m not sure if they’re aggressive - sorry.

I doubt they can climb over any substantial rock work since the worm is what moves the coral (and it typically moves by basically burrowing through the substrate and dragging the coral with it), but if the rock is really low/flat, then I'd guess that they could probably cross it.

Single polyp is the most common form, but (possibly dependent on collection location) ~41% of them have two or more polyps (38% two polyps, 3% more than two polyps).*

*Source:

High‐resolution imaging sheds new light on a multi‐tier symbiotic partnership between a “walking” solitary coral, a sipunculan, and a bivalve from East Africa

Marine symbioses are integral to the persistence of ecosystem functioning in coral reefs. Solitary corals of the species Heteropsammia cochlea and Heterocyathus aequicostatus have been observed to live in symbiosis with the sipunculan worm Aspidosiphon ...

www.ncbi.nlm.nih.gov

 

[Reefkeepers Archive]

I’m not sure if they’re aggressive - sorry.

I doubt they can climb over any substantial rock work since the worm is what moves the coral (and it typically moves by basically burrowing through the substrate and dragging the coral with it), but if the rock is really low/flat, then I'd guess that they could probably cross it.

Singe polyp is the most common form, but (possibly dependent on collection location) ~41% of them have two or more polyps (38% two polyps, 3% more than two polyps).*

*Source:

High‐resolution imaging sheds new light on a multi‐tier symbiotic partnership between a “walking” solitary coral, a sipunculan, and a bivalve from East Africa

Marine symbioses are integral to the persistence of ecosystem functioning in coral reefs. Solitary corals of the species Heteropsammia cochlea and Heterocyathus aequicostatus have been observed to live in symbiosis with the sipunculan worm Aspidosiphon ...

www.ncbi.nlm.nih.gov

Thanks! I have some other sandbed coral and if it's still available (by the next time my LFS orders coral) I wouldn't want for it to get stung by the trachyphyllia I have (that coral has been in my tank for a day and has already tried to kill my lobo twice) or sting the lobo/wilisoni. The one I'm looking at was collected from Australia.

 

[ptrusk]

I have had one of these for several years. Very hardy coral, the worm not so much. A few years ago, it occurred to me that I hadn't seen it out and about for a while. Couple weeks, month, I don't remember but it was a while. Went looking and found it in a cave. The worm was gone, dead or bailed, but it was gone. Coral still alive though.

I believe they do require feeding, but not frequently. It will let you know by pulling in polyps. Does not seem to like much light and closes up when I move it to the middle of the tank so I keep it on the side. Not much choice there with the worm, but as I said, the worm in mine is no longer present.

Never saw any sweepers or signs of aggression.

Very cool animal(s)!!