Mantis shrimp smashers damaged

[wwarby]

My peacock mantis shrimp seems to have damaged her smashers. I'm trying to get a photo to illustrate what I mean but she's not playing ball at the moment so I'll try to describe what I'm seeing. The smashers are red with a white bulb at the end that is ordinarily smooth on the front where it impacts anything the mantis is hitting. I've noticed however in the last few days that the front of that white bulb is slightly cratered - like the front layer of enamel has been smashed off.

She molted about three weeks ago and I have a photo of her from two weeks ago where the smashers still looked in tip top shape, so I don't think it's a case of smashing something too soon after a molt. She's been moved into a smaller tank for a couple of week now and seems fine, is eating well, smashing things when I give her shell food, so not sure if it's anything I need to worry about? I assume any damage to the smashers will get repaired in the next molt anyway but curious how this happened as I thought the tips of those smashers are supposed to be being studied by material scientists the military for their hardness and impact absorption properties. I'd be surprised if he injured herself bashing rocks or shells. Will post a photo if and when I can get one.

 

[MnFish1]

My peacock mantis shrimp seems to have damaged her smashers. I'm trying to get a photo to illustrate what I mean but she's not playing ball at the moment so I'll try to describe what I'm seeing. The smashers are red with a white bulb at the end that is ordinarily smooth on the front where it impacts anything the mantis is hitting. I've noticed however in the last few days that the front of that white bulb is slightly cratered - like the front layer of enamel has been smashed off.

She molted about three weeks ago and I have a photo of her from two weeks ago where the smashers still looked in tip top shape, so I don't think it's a case of smashing something too soon after a molt. She's been moved into a smaller tank for a couple of week now and seems fine, is eating well, smashing things when I give her shell food, so not sure if it's anything I need to worry about? I assume any damage to the smashers will get repaired in the next molt anyway but curious how this happened as I thought the tips of those smashers are supposed to be being studied by material scientists the military for their hardness and impact absorption properties. I'd be surprised if he injured herself bashing rocks or shells. Will post a photo if and when I can get one.

A picture would help - but I was going to ask about molting before I fully read your post. Is it eating? If so - I would merely wait to see - they would/should usually grow back?

 

[OneInchPunch]

Hmmm difficult to say anything without seeing it but I wouldn't be too worried as you say any damage should be repaired in the next moult. If he is still smashing happily they should be fine.

 

[wwarby]

Hmmm difficult to say anything without seeing it but I wouldn't be too worried as you say any damage should be repaired in the next moult. If he is still smashing happily they should be fine.

Yeah she’s definitely been punching stuff since I noticed this. I’ll get a photo sooner or later - you know how it is with mantis shrimps though - they keep the clubs tucked up under their belly a lot of the time. I’m certain the clubs will be replaced on the next molt, because I have the ones from the previous moly in a cupboard just a little concerned about how it happens though - wonder if she punched something very sharp, but I can’t think what. And on both clubs too.

 

[wwarby]

Managed to get a couple of photos of the damage today. Terrible quality images but hopefully enough to illustrate what I mean. I fed her a cockle in shell today and there’s new shell fragments outside the burrow so it’s obviously not a debilitating injury thank goodness. Any insight into how it happened would be appreciated though, in case there’s anything I can do to prevent a recurrence.

 

[OneInchPunch]

That's a new one on me? I can see the damage and if you forced me to guess I'd say its probably the result of an issue with their last moult where they weren't formed correctly but that is pure speculation. Has the damage stayed the same or does it look to be getting worse? If its not getting worse and they are happily using them I wouldn't worry too much.

Interested too see if anyone else has seen this before?

 

[wwarby]

Doesn’t seem to be getting worse but it’s hard to get a proper look at them - I can’t exactly just pick her up for a close inspection!

At a guess I’d say it happens at least two weeks after the molt, but I could be mistaken. I think it happened after her move to the new tank though. She seems fine so I’m not going to stress about it too much for now, I’ll just keep an eye on it.

 

[Stomatopods17]

I wouldn't worry too much about it, it'll repair them next molt if it doesn't self remove the arms.

The 'self mutilation' behavior is for healing, kinda like Coral banded shrimp can rip off their arms, stomatopods do it too but only if they're injured or *very* stressed, removing them sooner means they can start developing better ones, its their method of healing faster. First molt gives really small unusable raptorials, second molt gives weak slightly bigger ones, 3rd molt is back in full swing. Its natural they damage themselves occasionally and can look scary when their arms are being torn off (should be easy to get to eat frozen if both go), my O. havanensis did it after she jumped out of the acclimation cup a few hours after settling in.

There's a post by roy caldwell somewhere detailing it better on their molt cycles for this behavior. I don't think injuries speed up the timing of when they molt but it might.

 

[wwarby]

I wouldn't worry too much about it, it'll repair them next molt if it doesn't self remove the arms.

The 'self mutilation' behavior is for healing, kinda like Coral banded shrimp can rip off their arms, stomatopods do it too but only if they're injured or *very* stressed, removing them sooner means they can start developing better ones, its their method of healing faster. First molt gives really small unusable raptorials, second molt gives weak slightly bigger ones, 3rd molt is back in full swing. Its natural they damage themselves occasionally and can look scary when their arms are being torn off (should be easy to get to eat frozen if both go), my O. havanensis did it after she jumped out of the acclimation cup a few hours after settling in.

There's a post by roy caldwell somewhere detailing it better on their molt cycles for this behavior. I don't think injuries speed up the timing of when they molt but it might.

Mine rarely ever gets live food, so she's perfectly happy with frozen. She's had river shrimp a couple of times and she's murdered a couple of snails and a tuxedo urchin I put in as experimental CUC, but snails are expensive and I don't live close to the ocean to be able to pick up snails and crabs etc. on any kind of regular basis. She seems to like everything I give her - prawns, cockles, clams, small frozen fish - she's not fussy.

I'll keep an eye out for self mutilation, but so far she doesn't seem bothered by it, and I think the smashers have been this way for a week or two. I think mine is quite a mature mantis, she's only molted once in the three months or so I've had her and she was hidden away for a good 5 or 6 days for that molt. She's a on the large side too, I didn't see any noticeable change in size after the molt.

 

[wwarby]

Small update - Oatmeal finally shed those damaged smashers and they very much were damaged in the way it looked from the photos. Curiously she seemed to set up for a molt, covering her burrow entrances etc but the smashers seem to be the only part of the shell she’s cast off, and she’s dismantled the barricades now so I think she did a selective molt to replace just the smashers if that’s possible? Either way the new smashers look good to me.

 

[olonmv]

They looked like they’re rubbed raw.

 

[wwarby]

Small update - Oatmeal finally shed those damaged smashers and they very much were damaged in the way it looked from the photos. Curiously she seemed to set up for a molt, covering her burrow entrances etc but the smashers seem to be the only part of the shell she’s cast off, and she’s dismantled the barricades now so I think she did a selective molt to replace just the smashers if that’s possible? Either way the new smashers look good to me.

Yeah - the initial damage happened very soon after a molt and I don't know what caused it - she didn't seem bothered by it and continued to smash shell food, but perhaps over time the exposed area that was damaged wore thin.

The new ones look good to me - no obvious sign of damage but I'm going to feed her soft food for a week or so until I'm confident the new smashers are completely hardened.