Case of the Could-Be Ctenophore (or IS MY FUNGIA UNRAVELING??)

[Triple One]

hopefully i'm just overreacting.

a few days ago i noticed what look like jelly-fish sweeper tentacles trailing off of the smaller of my two fungia spp... the trailing strands are only really evident when the polyp is inflated and fleshy. when the razor brain exhales and the polyp tightens back down around the skeleton though, i can see a couple of single blades of bone poking out of the tissue right about where the wispy strings are attached. there are only a few stringy tentacles and the fungia appears to inflate normally, with all of its stubbier tentacles out and waving.

this is typically what it looks like, only these white stringier tentacles are a new addition:
<img src="http://a6.sphotos.ak.fbcdn.net/hphotos-ak-snc7/s720x720/293471_10100594323183472_10104357_56916882_644939740_n.jpg", alt="fungia string"/>

here's a close up to show the base of one tentacle at the left side of the red-bound area reaching across the disc:
<img src="http://a3.sphotos.ak.fbcdn.net/hphotos-ak-snc7/s720x720/384633_10100594323088662_10104357_56916879_96940604_n.jpg", alt="fungia string detail">

and here's a shot after it exhales, with the bony bits bordered (there are two exposed in the area on the right), but the tentacles not so obvious:
<img src="http://a5.sphotos.ak.fbcdn.net/hphotos-ak-ash4/s720x720/392987_10100594323053732_10104357_56916878_412986310_n.jpg", alt="fungia emaciatus"/>

i've read about coeloplanarians, and nothing about them really matches this from what i've seen (at least not with regards to the shape of their tentacles). i can't tell whether or not the strands are attached to the polyp tissue or if they're distinct animals, and i can't tell if the fungia is stressed or not (it doesn't honestly seem stressed...), so i don't know what to do. i guess strong currents could cause those little rips in the polyp to happen, but i don't think that's really the issue in this case, nor do i think my fish are pestering it. i'm pretty sure the Melanurus wrasse acts as more of a steward to the fungias, and none of the other fish really get that close to them. i did see my sailfin tang "test" one of these new trailing strings, but he did not rip it off, and it did not retract. he didn't seem too interested in the strings after that though, so maybe they did sting him. it's hard to be certain, but i don't think these strands are very reactive; if they are some sort of benthic ctenophore, possibly they are just parasites rather than symbionts...?

in case it helps shed some light, i feed the tank well, using a blend i made of brine and mysis shrimp, nori and macroalgae (sometimes solo, for the tangs...), squid, spirulina, silversides, raw whole table shrimp, garlic, and pure water, all pulsed into minced mash in an old cracked (fish only) Cuisinart, then frozen into thin chips. i believe the corals all filter plenty out for themselves but i still spot feed just in case. i recently upgraded my lighting from 216W to 432W of T5 (3 daylight, 1 purple, 4 actinic), which combines with the morning sun for a decently-lit sand floor (i have noticed a positive response in everything in the tank except one minor cyano outbreak that occurred right after i added the lights). and though i have moved the razor brains a few times when adjusting rocks or adding cupfuls of live sand to their area of the tank, as far as i know there have been no severe traumas to either one since placing them in the tank, and my water parameters are good: pH ~ 8.2-8.3, ammonia and nitrite undetectable, NO3 < 30ppm, PO4 ~ 0.25ppm, dKH ~ 9-10, Calcium ~ 420-440ppm, and about two weeks ago i had the LFS test my Magnesium at about 1550ppm. admittedly, the alkalinity has been hard for me to really stabilize (always about 10 degrees, +/-1, so it's not UNstable...). i know fungiids are picky about carbonate hardness being too high but it's not been higher than 11 degrees KH since before i added the fungia spp (steady for well over a month now).

obviously, i am confused. profusions, anyone? lay 'em on.

 

[Triple One]

So thanx for at least reading this, those of you who peeked...

I emailed Bob Fenner at Wet Web Media and he says these are a type of hydroid similar to some he has seen on several Scleractinians in the past. He also recommended I treat the coral, so I'll be working on getting that set up as soon as I can.

Have any of you other LPS-o-philes ever dealt with anything similar to this? Would love to know if anyone has any suggestions or (possibly more important) cautions? Don't want to lose this fungia to my amateur handling...

 

[greech]

Just reading this and after seeing the second pic I was going to say hydroids too so glad you have a positive ID. The second pic looks a lot like digitate hydroids. Do you notice them out more when the lights are dim or are they out pretty much all hours?

I may have missed it but are the fungia relatively new additions? Reason I ask is that any of the hydroids that I have had hitchhike into my tank in the past have not lived very long. Maybe they came in with the live sand? As you are probably aware, those "whips" flap around and catch food particles (in addition to the ability to sting). I don't know if a dip would help (thinking it would) but another step to take may be to feed the tank a little less or feed with larger foods so there is less for the hydroids to catch.

I hope these are as short lived for you as they have been for me and that your fungia make a full recovery.

 

[Triple One]

that makes two of us...

that makes two of us...

Just reading this and after seeing the second pic I was going to say hydroids too so glad you have a positive ID. The second pic looks a lot like digitate hydroids. Do you notice them out more when the lights are dim or are they out pretty much all hours?

I may have missed it but are the fungia relatively new additions? Reason I ask is that any of the hydroids that I have had hitchhike into my tank in the past have not lived very long. Maybe they came in with the live sand? As you are probably aware, those "whips" flap around and catch food particles (in addition to the ability to sting). I don't know if a dip would help (thinking it would) but another step to take may be to feed the tank a little less or feed with larger foods so there is less for the hydroids to catch.

I hope these are as short lived for you as they have been for me and that your fungia make a full recovery.

Thanx for your kind wishes Graham, and your good questions.

The fungia I'm worried about has been in the tank for about six weeks or so. Did your hydroids show up earlier than that?

As far as their activity cycle goes, I feel like they're fairly indifferent to the light. If anything, they seem to be out MORE during the day, because they're almost invisible whenever the plate exhales and the polyp shrinks in, and the fungia is always fleshier during the day (though it's still pretty fleshy at night). I really can't say though. That's actually one of the things that has me still sort of skeptical they're hydroids, and I haven't yet found an image online that really matches whatever these are. Everything I see seems to have a lot more branching going on (the digitate hydroids have branching capitate tentacles), whereas these things look to me to be more filiform or semifiliform... Here's a page with a good image to show what I mean:

http://www.ville-ge.ch/mhng/hydrozoa/antho/anthomedusae.htm

...except that that page is talking about jellyfish. I can't find anything about hydroids with filiform tentacles except ones that live in (branching) tubes or ones with that standard "hydra" look (almost like a zoanthid, or an umbrella that really loves to steal eyeballs).

Another thing that makes me wonder about their true nature: I tried pipetting them off one by one earlier tonight, and I still can't tell if it's even separate from the fungia tissue at all; they don't come off easily, and when they do the skeleton is exposed. Furthermore, they don't seem very responsive... I would expect the tentacles to retract when I mess with them with the pipet, but they just hang out like it's no big deal. But if this fungia is unraveling for some non-hydrozoan reason, I'm at a loss as to what it is. Its polyp seems otherwise happy, and any time I see or hear about someone's fungia receding, it doesn't look like this. Nothing else in the tank appears to be suffering (excepting the chronic dottyback attacks some of the fish endure...), and I don't know of any allelopathogens that would affect one fungia and not the other...

I hope it gets better too. I moved it to a slightly calmer spot in the tank to see if anything changes. Just out of curiosity, have you ever had any problems with your Melanurus nipping your LPS? I don't THINK mine is the cause of this damage, because she only really picks at my other fungia, and then only when it exhales and has a chunk of whatever stuck in the corner of its mouth. It's certainly not unraveling:

<img src="http://a3.sphotos.ak.fbcdn.net/hphotos-ak-ash4/384413_10100593589104572_10104357_56909006_397996915_n.jpg"/>

 

[greech]

No, my melenarus never touched a single polyp of any coral unless it was stealing some mysis out of its mouth!

I see what you mean in terms of the difference between digitates and what you have but I do think you have a similar form of hydroids on your fungia and where they have attached to your coral is where you are seeing the flesh recede from the irritation. The fact that they don't retarct when the lights or on or more importantly to touch tells me they are not digitates as well. Although I have no doubt that mine were digitate, I had the exact same issue with an acan that the hydroids colonized. The entire side of the acan where the hydroids "rooted" stayed retracted while the other side was fleshy and full. If you have the ability to touch them without retraction, I might be tempted to attempt physical removal if a dip or less aggressive methods don't work. If you do dip them look closely at the contact points with a magnifying glass and see if you can see any stolons (anchors/roots) while you have them out of the tank. If you can and there is no flesh at that point, you may want to take a very small screwdriver (eyeglass size) and scape the stolons off.

 

[seapug]

I have a large brain coral with one of those living in the base skeleton. It's been in my tank for over 1 year and doesn't seem bothered by it at all. Trying to kill it would probably be more stressful for the coral than letting it be so I've never messed with it.

 

[Triple One]

I have a large brain coral with one of those living in the base skeleton. It's been in my tank for over 1 year and doesn't seem bothered by it at all. Trying to kill it would probably be more stressful for the coral than letting it be so I've never messed with it.

Do you happen to have a picture SeaPug? I'm curious if it matches mine or if by "one of those" you mean a digitate hydroid like Graham mentioned, and also how strong the current is around the brain...

After trying to pipet off/out as many of the strands as I could the other day, I didn't see anything trailing off the fungia all day yesterday, but there are now at least 5 partially-exposed bone blades from where I removed the strands the day before. Towards the end of the evening yesterday though (when my timer switches off the daylight bulbs so only the blues and purple are on for the last few hours of the tank's "day"), the Fungia's mouth opened up and there appeared to be some coils of the strands inside. Couldn't get a clear picture unfortunately... Since I am still somewhat doubtful that these are definitely hydrozoans and I have similar-looking wisps naturally come out of the center of some of my mushroom anemones when they get bothered by my clumsy hands or too much current or whatever, I decided not to try and suck all the strands out of the fungia's mouth because I'm worried about damaging the coral if they are actually tissue from the fungia... Obviously I stressed the coral a ton already the day before, since it was literally only inflating the non-tattery 2/3 of the polyp for most of the day (a few times it had some parts of the damaged flesh filled with edema-looking bubbles but they were always fairly short-lived).

I'm just trying to observe and be patient at this point... Going a little crazy though.

 

[seapug]

Do you happen to have a picture SeaPug? I'm curious if it matches mine or if by "one of those" you mean a digitate hydroid like Graham mentioned, and also how strong the current is around the brain...

After trying to pipet off/out as many of the strands as I could the other day, I didn't see anything trailing off the fungia all day yesterday, but there are now at least 5 partially-exposed bone blades from where I removed the strands the day before. Towards the end of the evening yesterday though (when my timer switches off the daylight bulbs so only the blues and purple are on for the last few hours of the tank's "day"), the Fungia's mouth opened up and there appeared to be some coils of the strands inside. Couldn't get a clear picture unfortunately... Since I am still somewhat doubtful that these are definitely hydrozoans and I have similar-looking wisps naturally come out of the center of some of my mushroom anemones when they get bothered by my clumsy hands or too much current or whatever, I decided not to try and suck all the strands out of the fungia's mouth because I'm worried about damaging the coral if they are actually tissue from the fungia... Obviously I stressed the coral a ton already the day before, since it was literally only inflating the non-tattery 2/3 of the polyp for most of the day (a few times it had some parts of the damaged flesh filled with edema-looking bubbles but they were always fairly short-lived).

I'm just trying to observe and be patient at this point... Going a little crazy though.

I don't have any photos but it looks exactly like what you have. Current around the brain is a very gentle alternating surge on a 1 second cycle.

The damage that's occurring to your fungia in the effort to remove it is precisely the reason why I've left it alone on mine. Sometimes it's best to just let things be. Don't kill with kindness.

 

[Triple One]

Sometimes it's best to just let things be. Don't kill with kindness.

I agree. I was hesitant to do anything to begin with, and after the damage I already did I haven't messed with my fungia (since the traumatic pipet episode) and it is doing better; the mouth looks normal again and the damaged side of the polyp is mostly inflated again. I think also that the hydrozoans seem to have been curbed by the mechanical treatment (at least for now), if hydrozoans is what they indeed are/were. I am confident that the fungia will recover though. It's a tough little coral.

Sorry if I'm :deadhorse: by asking for so many details seapug, but since you have something similar in your tank I'm curious about your situation (and I very much appreciate your thoughts!). You said the string has been on your brain's base skeleton for over a year; I'm curious if the coral's polyp surrounds the strand or if the string is on a part of exposed skeleton, and if it's the latter, was the brain already receded in that spot or did you notice the skeleton exposure appear at about the same time you first noticed the strand?

 

[Triple One]

Rest In Pieces

Rest In Pieces

the plate was infested. tried fragging to save the "good" part only to find the inside completely inundated with hydrozoans, and already starting to stink of death. it's a shame: i couldn't even leave the dead pieces in the tank and hope for a phoenix fungia because i wouldn't risk the doom tentacles spreading.

it was a beautiful piece...