Crab lavae explosion!

[Arcticreef]

While trying to train my sun coral tonight I noticed a swarm of 1-2 mm white dots swarming the light. Like probably 500 in a few seconds just in that area. Have never seen these before. I caught some and put under the microscope. Managed to determine it is crab lavae. One of the online docs says it's only for a short time in the water column as part of their lifecycle.

My question to the zoologists is, if these guys survive are they going to become problem crabs...and how long before I know what kind of crab it will be? my hermit died about 2 months ago and I removed a gall crab from a new neon trumpet a month back. I sure hope these aren't gall crabs.

 

[blaxsun]

Neat (well, not neat if you end up with a bumper crop of gall crabs - but still kind of cool).

 

[DaJMasta]

You certainly don't have to worry about them becoming hundreds of pests, between the powerheads and the hungry mouths in the tank, they likely won't last for more than an hour. That said, they'll be some good food for things in that time, and odds are good they will spawn again if you wanted to try and catch and raise them (though it would likely be a challenge).

I haven't seen these ones in my tank (and I've had half dozen or so invert spawns examined under a microscope), but I would guess either a type of hermit or mithrax crab. Could absolutely be something else entirely, it's very difficult to discern larvae for many growth stages after hatch and they don't necesessarily look anything like the adults, but they're common enough inhabitants and have larvae that could look like that.

 

[Arcticreef]

You certainly don't have to worry about them becoming hundreds of pests, between the powerheads and the hungry mouths in the tank, they likely won't last for more than an hour. That said, they'll be some good food for things in that time, and odds are good they will spawn again if you wanted to try and catch and raise them (though it would likely be a challenge).

I haven't seen these ones in my tank (and I've had half dozen or so invert spawns examined under a microscope), but I would guess either a type of hermit or mithrax crab. Could absolutely be something else entirely, it's very difficult to discern larvae for many growth stages after hatch and they don't necesessarily look anything like the adults, but they're common enough inhabitants and have larvae that could look like that.

Thanks for the feedback and I agree they most probably won't last...or so I hope. I have a good video but it won't post here. I could try and catch and rear a few to see what they become. It must mean I have an adult crab lurking somewhere in my rockwork.

 

[mnreefster]

Just came across this. Pretty cool stuff; wish I knew how to share the video. There were thousands of them. Bunch of twisting sperm. Cardinalfish were going crazy lol