ID this snail eating red legged crab please?

AstroMelly · Dec 5, 2021

We just bought our first batch of livestock for our first marine tank yesterday.

We bought 6xCerith, 6xTrochus, 6xNassarius and 6 red legged hermits. Looks like we are losing the crabs slowly. I think 3 are already gone (24 hours). I caught a Nassarius smothering one, not sure if he was snacking on him, then he left. Maybe the crab was already dead, I now know they are carrion eaters. Then an hour or so later this guy came along and dragged the crab out of his shell and is now eating him. I did some reading on Nassarius and it sounds like the one in the picture might actually be a Welk Snail (pest), sold to us in error perhaps?

Ideas please? I’d like to get it out of the tank if so as we also got some blood shrimp that were a bit pricy!

Thanks!

elysics · Dec 5, 2021

Snails dragging hermits out of their shell. That's a new one for me

AstroMelly · Dec 6, 2021

I think the consensus is that the crab died or was dead soon after arrival.
I got some positive ID as a Nassarius on a fb group, in which case he was just doing his job. I was worried he may have been a whelk snail but seems he is just a different variety of Nassarius (I hope!).

blaxsun · Dec 6, 2021

AstroMelly said:
I think the consensus is that the crab died or was dead soon after arrival.
I got some positive ID as a Nassarius on a fb group, in which case he was just doing his job. I was worried he may have been a whelk snail but seems he is just a different variety of Nassarius (I hope!).

Pretty sure the crab was dead. Nassarius snails are opportunistic feeders and will never pass up a free meal (mine will eat virtually anything).

I have two types of nassarius snails and it looks like the regular version (and not the orange spotted variety I also have).

AstroMelly · Dec 6, 2021

Yes I am coming round to that idea - 5 of our 6 Nassarius are smooth shelled with translucent syphons, this one is just a different variety I think - as you say - the 'regular' version. I'm impressed by their speed - as soon as we fed they were up and out of the sand - scooting across the sand like a bunch of crazy zombies! Very quick at homing in on their 'targets' as well. Great little critters!