Aiptasia reproduction questions

[Xylotrupes]

Hello,
This might sound strange for most of you but I am trying to get a better grip on Aiptasia reproduction.

I belong to a scientific laboratory that uses Aiptasia as a model system. Of course it is very easy to make Aiptasia reproduce asexually by pedal lacceration. However, we are so far struggling with the sexual reproduction. Sexual reproduction is very important if we want to answer specific questions.

We are able to induce spawning of Aiptasia (using blue light and a temperature shift from 26° to 29°C) and we get lots of planular larvae but so far only a single case is known in which a larvae completed metamorphosis and became an adult again.

In many forum posts I read it seemed like the most natural thing that the Aiptasias spawn and settle down when they overgrow an aquarium but so far it never worked in the laboratories around the world.

My question is if anyone here has ever observed Aiptasia larvae in his tank (approx. 100 µm) and if yes if you have ever seen them settle down and become adults?
If so maybe you have observed specific substrates they like to settle down on.

 

[sfin52]

Do you know what the larvae eat.

My aptasia started on lr. I added peppermint shrimp to the tank and it has been aptasia free.

There’s a member that has an aptasia and mojo tank. I Can’t remeber their name, Sorry. You could try searching for them. Sorry I can’t be more help.

 

[Xylotrupes]

Well that is a good question, We only know from coral larvae that they seem to take up the symbionts and then settle down. without having to eat anything. So far we thought that maybe we have to supplement amino acids which they might take up from the water directly.
I guess that everything they need might need would be available in normal Aquarium water or naturla sea water though (both of which have been tried already)

 

[40B Knasty]

Hello,
This might sound strange for most of you but I am trying to get a better grip on Aiptasia reproduction.

I belong to a scientific laboratory that uses Aiptasia as a model system. Of course it is very easy to make Aiptasia reproduce asexually by pedal lacceration. However, we are so far struggling with the sexual reproduction. Sexual reproduction is very important if we want to answer specific questions.

We are able to induce spawning of Aiptasia (using blue light and a temperature shift from 26° to 29°C) and we get lots of planular larvae but so far only a single case is known in which a larvae completed metamorphosis and became an adult again.

In many forum posts I read it seemed like the most natural thing that the Aiptasias spawn and settle down when they overgrow an aquarium but so far it never worked in the laboratories around the world.

My question is if anyone here has ever observed Aiptasia larvae in his tank (approx. 100 µm) and if yes if you have ever seen them settle down and become adults?
If so maybe you have observed specific substrates they like to settle down on.

This may sound even a little weirder, but if you irritate them. They go into a protect and populate mode to ensure survival. Myself and a lot of members say that they try to do a removal of them and end up with more. I don't know if maybe chopping one up and having the cells settle in a tank is the answer, but it sounds like a sensible one to me.
Since they have zooxanthellae which is the algae that the animal itself shares a symbiotic relationship with to get its energy from the Sun. A good color spectrum would be with an Actinic T5 bulb 400-450nM to feed it with photosynthesis. Zooplankton and phytoplankton I would imagine is probably the best food source for them. Live rock with some porosity for the cells to find a hole in to hide and grow in.
Just found this little piece for you in an article:
Breeding and Reproduction: Propagating aiptasia anemones is fairly easy, just cut a piece off and it will grow. Anemones in general can multiply by sexual and asexual means. Aiptasia will multiply asexually by fission, which is where a tiny bit of tissue detached from the foot quickly develops into a new and complete anemone. Aiptasia anemones will tolerate their own "clones", and these anemones are very prolific. This is why it is very difficult to physically remove these anemones from a rock. Any remaining tissues quickly multiply into to new specimens.

Studies of A. pallida and A. pulchella have determined that individuals are dioecious, meaning that individuals are of separate sexes. However, sexual reproduction has not been described for the species. They may also reproduce using male and female sex glands. This results in the production of ciliated planula larvae which will eventually fall to the sea floor, develop a pedal disk, then begin to grow into a new anemone.

 

[Xylotrupes]

Thank you very much for the answers so far.
However the general mass breeding of Aiptasia is not really my concern because pedal lacceration and as you observed as well just cutting the works fine.
Unfortunately for some laboratory techniques we have to go into the larvae (e.g to inject certain genetic constructs into the eggs if we want to make a mutant line) so it is necessary to know how the larvae develop back into adults so we can keep our mutants alive (the larvae only survive for 2-3 weeks). Otherwise we have to create mutants every week (which takes a lot of time and money).
As I also wrote production of larvae is also not a problem as there are very robust protocols which we can use to make them spawn every month (even without irritating them).

As the article you quoted stated "sexual reproduction has not been described for the species" this is the big question. We can observe sexual reproduction up to the larvae stage but we can not complete the life cycle. However we can be fairly certain that Aiptasia can reproduce sexually in the wild.
It is very hard to follow Aiptasia larvae in the ocean to see where they might settle down so the logical next step would be to look in reef aquariums. Maybe someone here has taken the time to observe Aiptasia in an effort to get rid of them.
It would e.g. be really interesting to know if the Aiptasias you have in your tanks do produce larvae when you irritate them (so if they spit out eggs do they develop into mobile larvae (approx. 100um in length) and do these larvae find a place to settle down. (Maybe someone here has tried to catch the eggs of his Aiptasias to prevent them from spreading? and by chance kept them in a glass of water/ unused aquarium and then found thousands of tiny Aiptasias in there?)

I guess it might be interesting for many people here if catching the eggs before they can spread actually can prevent a hugh spreading of Aiptasia or if it is completely unessecary because the larvae can not develop anyway in a reef aquarium.

So to make it clear I a not generally interested in how to breed Aiptasia en mass (we have quite good culture systems going) but rather in the specific question how to make the larvae settle down and develop into adults.

 

[40B Knasty]

Thank you very much for the answers so far.
However the general mass breeding of Aiptasia is not really my concern because pedal lacceration and as you observed as well just cutting the works fine.
Unfortunately for some laboratory techniques we have to go into the larvae (e.g to inject certain genetic constructs into the eggs if we want to make a mutant line) so it is necessary to know how the larvae develop back into adults so we can keep our mutants alive (the larvae only survive for 2-3 weeks). Otherwise we have to create mutants every week (which takes a lot of time and money).
As I also wrote production of larvae is also not a problem as there are very robust protocols which we can use to make them spawn every month (even without irritating them).

As the article you quoted stated "sexual reproduction has not been described for the species" this is the big question. We can observe sexual reproduction up to the larvae stage but we can not complete the life cycle. However we can be fairly certain that Aiptasia can reproduce sexually in the wild.
It is very hard to follow Aiptasia larvae in the ocean to see where they might settle down so the logical next step would be to look in reef aquariums. Maybe someone here has taken the time to observe Aiptasia in an effort to get rid of them.
It would e.g. be really interesting to know if the Aiptasias you have in your tanks do produce larvae when you irritate them (so if they spit out eggs do they develop into mobile larvae (approx. 100um in length) and do these larvae find a place to settle down. (Maybe someone here has tried to catch the eggs of his Aiptasias to prevent them from spreading? and by chance kept them in a glass of water/ unused aquarium and then found thousands of tiny Aiptasias in there?)

I guess it might be interesting for many people here if catching the eggs before they can spread actually can prevent a hugh spreading of Aiptasia or if it is completely unessecary because the larvae can not develop anyway in a reef aquarium.

So to make it clear I a not generally interested in how to breed Aiptasia en mass (we have quite good culture systems going) but rather in the specific question how to make the larvae settle down and develop into adults.

When I boiled hot water in a microwave and used a 5mm syringe. Pressed the water into its spot. They hid for a bit. Then I tried it with a hypodermic needle into the mouth/stem and scraped with the needle. Those 2 went away. But showed up in other areas 2 weeks later. The new ones were 2x bigger than the ones that got injected.
Then I pulled the rocks, dried them for 3 days, and threw them in a deep frier outside filled with water for an hour. Then let it dry for another 3 days. That worked for killing it.

 

[Xylotrupes]

When I boiled hot water in a microwave and used a 5mm syringe. Pressed the water into its spot. They hid for a bit. Then I tried it with a hypodermic needle into the mouth/stem and scraped with the needle. Those 2 went away. But showed up in other areas 2 weeks later. The new ones were 2x bigger than the ones that got injected.
Then I pulled the rocks, dried them for 3 days, and threw them in a deep frier outside filled with water for an hour. Then let it dry for another 3 days. That worked for killing it.

Well that is definitely a valuable information if I ever want to get rid of mine...so far just taking them all out and cleaning the whole tank with a sponge and distilled water worked fine as well though (We do not have any sand or rocks in our culture tanks so that is a bit easier) but thank you very much anyways

 

[NanoCrazed]

Soooo... I had exactly what your looking for as I have been documenting an odd larval looming thing in on3 of my tank that later proved to be aiptasia.

Unfortunately, my photos were lost due to a failed cloud backup and a stolen phone.

What I can tell you, is when I first noticed the larvae it clung to my glass and looked more like a hydra of sorts. Now and then, it would move and the. I finally found it plus several more in my filter media where they settled and started growing. (Coincidentally, I just exposed that portion of my media to dry as I wasn't able to extract them to my pest tank and did not want them in my primary live rock maturing tank).

Baed I on this, I would suggest drawing the tank water through sponge media ahead of your filtration pump to provide an easy footing. To give ypu some design considerations, in that tank where the above happen, I used a Fluval Spec /Evo 5 (literally the same tank with exception of lighting).

In any case, I run a pest tank filled with all sorts of things like aiptasia. If you're interested, I can photo document things that next time I happen to see any larva or spawning

Interesting side note, I just found a tiny one the other day under a plug with two small pink masses that look like pellets inside its tube... not sure if they are indeed pellets or some other material that is foreign or belonging to that particular aiptasia. :/

 

[Xylotrupes]

Soooo... I had exactly what your looking for as I have been documenting an odd larval looming thing in on3 of my tank that later proved to be aiptasia.

Unfortunately, my photos were lost due to a failed cloud backup and a stolen phone.

What I can tell you, is when I first noticed the larvae it clung to my glass and looked more like a hydra of sorts. Now and then, it would move and the. I finally found it plus several more in my filter media where they settled and started growing. (Coincidentally, I just exposed that portion of my media to dry as I wasn't able to extract them to my pest tank and did not want them in my primary live rock maturing tank).

Baed I on this, I would suggest drawing the tank water through sponge media ahead of your filtration pump to provide an easy footing. To give ypu some design considerations, in that tank where the above happen, I used a Fluval Spec /Evo 5 (literally the same tank with exception of lighting).

In any case, I run a pest tank filled with all sorts of things like aiptasia. If you're interested, I can photo document things that next time I happen to see any larva or spawning

Interesting side note, I just found a tiny one the other day under a plug with two small pink masses that look like pellets inside its tube... not sure if they are indeed pellets or some other material that is foreign or belonging to that particular aiptasia. :/

Hello,
Wow that is great. I would be fantastic if you could make some pictures (also of the adults) of what you see so I could compare it to what we have in the laboratory. If the larvae looks like a Hydra already it is however likely that it is already a small adult.
I will include a microscopic picture of a larvae with some symbiotic algae (Source: http://guselab.de/research/).
As I said they are tiny (100 x 80 microns) we normally look at them at 4 - 8 x magnification to see them swimming around (the picture was taken at 400 x though.)

Still it is well worth a try to have sponge media and a filter pump in the setup.
As I understand it is basically a secondary tank without much light through which your display water is running while being filtered right?
Thank you very much so far.

 

[AcanLord.com]

Hello,

Been following along here. Very interesting. If you don't mind my asking, what would be the benefit of modifying a mutant variety of the species?

 

[AcanLord.com]

Hello,

Been following along here. Very interesting. If you don't mind my asking, what would be the benefit of modifying a mutant variety of the species?

 

[AcanLord.com]

Sorry for the double posts. major issues with my phone.

 

[K. Steven]

Aiptasia is an important model organism for studying cnidarian endosymbiosis in molecular, cellular, and evolutionary-developmental ("evo-devo") biology.

http://www.pnas.org/content/112/38/11893

 

[Xylotrupes]

Hello,

Been following along here. Very interesting. If you don't mind my asking, what would be the benefit of modifying a mutant variety of the species?

Sorry I did not see the post.
the as K.Steven said already Aiptasia is a model system to understand coral biology. It is very complicated to work with corals in the laboratory becasue they are endagered and hard to keep and take ages to reproduce.
Aiptasia is much easier but it is related and also symbiotic (it even has the same symbionts) ... think of it in the same way as laboratory mice as models for humans.

THere are still a lot of questions we need to understand about corals... how their symbiosis works, how they reproduce, how they grow...
to answer those questions we try to look in Aiptasia and then try to use what we learn there and try it on corals... again in the same way as when we research mice to cure a human disease.

my personal project is to learn more about the reproduction... when we understand how that works in corals we could for example trick the corals in captivity to spawn more often which would help a lot in breeding corals (either for fish tanks or to conserve them if global warming increases) we could also try to learn how to make them more resistant to raising sea temperatures.
and a lot of other questions...
and of course it would be much easier to breed nudibraches large scale if the Aiptasia supply was unlimited... so their prices would drop

 

[Kristin Thomas]

I'm hoping someone on this thread can identify this? Aiptasia? They are all over the glass of my pump chamber, but nowhere in my display?

 

[Xylotrupes]

The pictures are not really great but to me they look like Aiptasia

 

[Mical]

Do you mean like these? I moved some chaeto to my quarantine tank and with just moderate flow these guys appeared in about 10 days.

 

[Xylotrupes]

Well those are definitely Aiptasias but the are way to big to be recently hatched from eggs. Those are a few weeks old in my experience probably they came from pedal laccerates or regenerated from some pieces that were ripped off a bigger one.

 

[sixty_reefer]

Hi, old thread just wondering how did you advance on the subject. Did you got to be successful in the end?