Mantis Shrimp Molting?

[Rewd]

I believe I have an N wennerae that hitchhiked in on my Florida Keys live rock and I absolutely love this little thing. It has coexisted with 7 fish of various sizes with zero problems since May of last year. I've noticed more empty snail shells in this tank than my other tanks, but with an LFS 5 minutes away, I have not minded having to buy additional CUC for this tank lol. I hand feed him with tongs almost every day and he is not particularly shy or reclusive anymore, at least until about a week ago. He seems to have disappeared entirely. I don't see him at feeding times and I don't see his head poking out of any of his normal hiding holes. Is it unusual for a mantis to disappear for a time while they molt or something? I am definitely concerned as he was one of my favorite critters in the tank.

Only water quality issues were my alk and ca got a little low when I wasn't monitoring it as much as I should. Alk dropped to 5.4 and ca dropped to the mid 300s. Both are back up now after very slowly dosing a little extra. I haven't tested my nitrates and phosphates in a while so I can't provide that info at the moment. salinity 1.025.

 

[SlugSnorter]

I believe I have an N wennerae that hitchhiked in on my Florida Keys live rock and I absolutely love this little thing. It has coexisted with 7 fish of various sizes with zero problems since May of last year. I've noticed more empty snail shells in this tank than my other tanks, but with an LFS 5 minutes away, I have not minded having to buy additional CUC for this tank lol. I hand feed him with tongs almost every day and he is not particularly shy or reclusive anymore, at least until about a week ago. He seems to have disappeared entirely. I don't see him at feeding times and I don't see his head poking out of any of his normal hiding holes. Is it unusual for a mantis to disappear for a time while they molt or something? I am definitely concerned as he was one of my favorite critters in the tank.

Only water quality issues were my alk and ca got a little low when I wasn't monitoring it as much as I should. Alk dropped to 5.4 and ca dropped to the mid 300s. Both are back up now after very slowly dosing a little extra. I haven't tested my nitrates and phosphates in a while so I can't provide that info at the moment. salinity 1.025.

they can disappear for a while when molting. It will likey go after fish once it feels it is large enough, so watch out.

 

[Stomatopods17]

If he's molting there will be bits of rubble/rock/shell/whatever covering the cavity.

N. wennerae closes their burrow at night with materials they can find or chip of the rock itself. A molt would mimic this for a longer period of time.

Not sure on the duration but one of my N. wennerae I kept in a sump, after a few weeks of inactivity I presumed dead, another month or maybe even 2 later I was showing a family member my stomatopods and then showed them where I used to have another one and before I finished the sentence about it being long gone it peeped out of the hole, either it took that long to molt or it survived on the local refugium amphipods.

 

[Rewd]

If he's molting there will be bits of rubble/rock/shell/whatever covering the cavity.

N. wennerae closes their burrow at night with materials they can find or chip of the rock itself. A molt would mimic this for a longer period of time.

Not sure on the duration but one of my N. wennerae I kept in a sump, after a few weeks of inactivity I presumed dead, another month or maybe even 2 later I was showing a family member my stomatopods and then showed them where I used to have another one and before I finished the sentence about it being long gone it peeped out of the hole, either it took that long to molt or it survived on the local refugium amphipods.

This is kind of what I'm thinking and hoping is occurring. Did you ever have any of your Wennerae's with fish? He's already about 2" or so, I don't see him being big enough to take down any of my fish but I know it's a risk. If he isn't dead, I'd prefer to keep him in the main tank lol.

 

[Stomatopods17]

Rule of thumb with mantis is don't expect consistency. If you're willing to risk it vs. making sump space/nano that's up to you.

There's an o. scyllarus right next to me threat posturing me for the past hour, I have no clue what her problem is, but the blue yellow tail damsel seems fine swimming close to me in her ticked off sightline. They've been together for about 2 and a half months.

Similarly I had another o. scyllarus live with damsels, sharing burrow space even, 2 domino damsels disappeared but the velvet damsel (who'd I've believe killed them more than the mantis, it was 3 damsels in a 30 gallon) was with him the whole time until his passing. I actually would hand feed and pet this one without any fear, he was a very chill but easily destroyed clams so there wasn't anything wrong with him.

A G. chiragra I tried mercy killing a damsel with (which was being bullied to death by another damsel...), and the sad part is she didn't even interact with it at all, despite dropping it in like a feeder and the fish being too injured to swim correctly, fish died naturally without intervention which I hated to see.

The N. wennerae that was in my sump I gambled with 2 emerald crabs overnight, no casualties.

...and then we have the O. scyllarus I had at the same time as the 2nd one mentioned, that didn't appreciate the concept of life breathing her air and killed anything and everything that twitched. The N. wennerae that actually broke out of the kritter keeper at my LFS, then rampaged their emerald crabs, and my very first O. scyllarus who only lasted about a day with damsels then infront of everyone suddenly started smashing one. My first mantis (a G. tern) was exceptionally aggressive too, all my other G. terns were chill but this particular one was evil enough to swim up and strike the glass if you stuck your finger on it. The other N. wennerae I had did escape by breaking through a breeding container and get lose in one of my display tanks filled with fish but there was no casualties and I removed it immediately. All the other stomatopods were solitary and never tested fate with, my O. havanesis managed to kill a hermit crab without either raptorial appendages so I never tested it in my large display like I considered doing until it healed.

Large fish I'd worry more about spooking it and causing a defensive strike. When it comes to fish 1 injury is all it takes to cause an infection and kill them. Behavior can swing around molting times as well, or even based on age.

 

[Rewd]

I did see it defensive posture once but I don't think anyone was actively going at it, just suddenly spooked. Ironically, my red mithrax crabs hitchhiked along with it have faired just fine, but a large red gorilla crab (that I intended to trap and remove) was discovered upside down, twitching, clinging to life, missing several legs and with a few dents in his shell. I wonder who was responsible for that? The world may never know.