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-   -   So how long will it take for my stomatopod to molt and what is it doing? (

Koshmar 11/08/2008 07:44 PM

I guess I'll create a brand new thread soon to Id this little guy or gal, (I can't even be sure of the sex anymore). I guess my lfs mislabbled it "red peacock mantis shrimp." The important part is that I got a pic of the white/clear portion of the raptorial appendages. That is what I have a question over, is it indicative of a molt or something else?

On a seperate note, is molting linked in any way to the lunar phases? After a M.S. molts, if it strikes a hard bodied creature, does it interfere with the harding process of the new exoskeleton?

Gonodactylus 11/09/2008 02:05 AM

Well, we know it is a gonodactylid.

Most stomatopods molt in relation to a lunar cycle. Some molt on the full moon, others on the new moon. It depends on the local tidal cycle as well as the depth at which the animal lives. How this is controlled is a bit of a mystery, but animals in my lab often seem to molt synchronously and I suspect that it is related to lunar illumination (the lab has lots of windows). We know that the synchrony last for a few months even when the animals are held in rooms without windows, but we see synchrony in animals that have been in the lab for years. That would seem to be too long to remain synchrony without an external cue.

Stomatopods usually do not strike when molting since the appendage cannot function until the cuticle hardens. If you induce striking prematurely, the appendage can literally tear itself apart.


Koshmar 11/09/2008 11:48 AM

Does artificial light have any impact on the molting cycle? If the duration of the lighting is changed often will the molting process be affected?

On a seperate note, I have been told that if a M.S. strikes with its raptorial appendage while out of water the said appendage will rip clean off and fly off of the animal. Is there any truth to this? I know that the density of water and air are vastly different but I find it hard to believe that the M.S. could "shoot" its arm clean off if it struck in the air at something.

Reefologist 01/23/2009 05:04 PM

So all things considered how long should I expect my little buudy to live.

I may have missed the info, sorry if I'm asking an already answered
question. What is the average life expectancy of a peacock (Odontodactlis
ylus scyllarus) Mine lives in a 120gal tank with about a 6" sanbed and the rockwork was placed to provide him an optimum enviornment for climbing as well as over head protection. He is fed selcon soaked shrimp as well as hermit crabs and many different types of snails so he can eat a natural diet and also keep his bashing appendages strong in working order

Gonodactylus 01/23/2009 05:10 PM

The quick answer is no one knows. THere have been no demographic studies done on this species. From experience in the lab, I don't think they are that long-lived. My guess would be 6-8 years, but I would like to hear from anyone who has kept one longer.


Reefologist 01/23/2009 05:28 PM

Wow, that was the fastest response in RC history possibly. First off thank you Dr.Roy for your dedication to stomatopods and helping those of us who are fascinated by these wonderful creatures. I am an audio engineer, I provide sound reinforcement for the Louisville Orchestra as well as many well known musicians. I am very passionate about audio and I can honestly say that I love my job, as I can tell how passionate you are about your work, I guess what I'm saying is for all of us who you educate and mentor for no financial benefit or rewards except helping hobbyists and for that you should receive the Reef Central Nobel Prize if there was such a thing. My O.S. Is either in the process of molting or he has passed on to wherever it is that Stomatopods go (other than the bellies of nassarius snails, and serpent starfish)when they die. He was at least 6" long when I got him approx 2 years ago so if he doesn't appear from his burrow soon I guess ill have to make funeral arrangements for his departure. Thanks again for your very rapid response. Your friend and admirer, Reefologist

crysis 01/24/2009 09:55 AM

+1 Reefologist. Excellent post. My O.S. is close to 4" long, and I believe just completed a molt. I have no evidence of this however, except that I saw him twirling a rapt in his mouth last night, which scared me (see my post) only to find that after this was done he came out of his burrow and both rapts were intact. I was at work for 13 hours yesterday, so much could have happened. Could he have eaten his molt in that time period after molting? It was somewhat dark, only blue moonlights, but I couldnt find the rapt molt after he came out, so he could have left it in his burrow. He appears healthy and hopefully he will be a little more active now.

schackmel 05/09/2009 10:14 PM

great post! Thanks for the info. I have a 10" or so peacock mantis He has molted about 4 times since I had him (a little under a year!) He is very active, eats well etc.

However the last 2 molts were very hard on him. The first one took over a week for him to completely molt. I would see him swim out one day wiht a piece of old shell, then a couple days later his swimmettes, then a couple days later another piece. His tank is in my office so I saw more of him.

I turn off his lights when he molts to reduce his stress. I even turn off the other tank lights during the time.

On his last molt I thought for sure he was going to die! I come in and he is on his back in the middle of the tank kicking and kicking his swimmettes. He usually closes himself in his den for days when he molts. I turn off his lights and leave him be. He remained on his back out in the open for the remainder of the night. The next day he went back to his den and molted for many many days...2 weeks in fact. He would throw pieces of his shell out of the den during that time.

I guess my question is.....will his molts continue to get harder on him? I have no idea how old he is but like I said he is a good 10". I fret over his molts and i fear he will die in the next one.

He eats very well. He loves krill, silversides, squid not so much, whole raw shrimp, etc. I give him a couple large turbo snails to graze on at least a couple times a month. I soak all his food in Selcon or GVH. Any ideas?

Gonodactylus 05/11/2009 08:37 AM

First, let me say that the largest O. scyllarus ever recorded was 175 mm, right at 7 inches. Anything larger than 6 inches is very large for this species and most have trouble molting.

The fact that pieces were thrown out in stages does not mean that he was molting over a long period. Animals often bury their molt skin and then gradually dig it up - sometimes eating the softer parts.

As I've said before, most stomatopods in captivity die during a molt and the older the animal, the more likely it will happen. Such is life (and death) for a stomatopod.


schackmel 05/11/2009 09:45 PM

thanks for the response! the actual size was an estimate...sounds like I was way OVER :mixed: He is larger then all that I have seen before but I am sure he is not THE largest.

I unfortunatly am prepared that he will eventually die...but hoping he will not! Glad to hear that he probably buried his molt! Makes sense:eek1:

sanchoy 07/05/2009 12:33 PM

10 inches!!!

You probably have the record than

uberbatman 07/24/2009 03:01 PM

Heres a video i took of mine during her last molt.


SMaxwell 08/19/2009 09:23 AM


<a href=showthread.php?s=&postid=15410407#post15410407 target=_blank>Originally posted</a> by uberbatman
Heres a video i took of mine during her last molt.


WoW! Amazing video you got there. Thanks!

Aqua_boy 12/23/2009 06:54 AM

Great collection.........

Aqua_boy 01/05/2010 04:19 AM

Good info........

marcin11379 02/04/2010 07:55 PM

good info...................

Pamelahaley 11/07/2010 07:53 AM

I know you've stated a mantis will bury and eat the molt but, would a mantis, like some crabs and shrimp I've had, use the molt as a decoy outside the lair until the shell hardens?

Dana42078 11/28/2010 01:39 AM


Originally Posted by SMaxwell (Post 15555860)
WoW! Amazing video you got there. Thanks!

Second that and thanks for all the great info.

Gonodactylus 01/26/2011 09:12 AM

A stomatopod molt doesn't look much like a live one. I don't think it would be effective and there is no evidence that they deliberately place the molt skin outside the entrance.


Dana42078 02/09/2011 10:57 PM

Good info, my mantis finally molted after a month and a half of having him. He seems to be ok so far but it just happened a few hours ago while i was at work. He is about 4 inches long.

kiel 04/20/2011 11:38 AM

excellent info..

i just lost a gonodactylus smithii during his first malt in the system..truly awesome creatures, was a privelage to share time in such close proximity. just hope i wasn't too much of a stress factor on his last days

StephLionfish 07/05/2011 09:54 PM

When Mantis shrimp molt, are they more "delicate" than say... a cleaner shrimp? It seems as though when Mantis shrimp molt, it's a much bigger "deal" than when a hermit crab or peppermint shrimp molt....?

Gonodactylus 07/06/2011 12:19 AM

Yes, stomatopods take longer to recover and are incapacitated more probably because the stomatopods have more armor that takes longer to replace.


Dana42078 07/21/2011 01:03 PM


Originally Posted by Gonodactylus (Post 8479076)
Nothing special except don't bug them by trying to see what is going on in the cavity. Also, try to keep tank parameters constant. This is not a time to allow the temperature to change, to adjust the salinity or probably even clean the sand. By the time the molt is a day or two away, the animal has stopped eating and I would not recommend adding nutrients or supplements. (On more time - where did this myth come from that stomatopods need extra iodine?)

As for how long does it take for a 15 cm O.s to molt - about a minute. If you were asking how long is it between molts, it depends on how much it is eating and for females, if she lays eggs. The average would be every 3 or 4 months, but I've seen well fed large O.s molt in every two months and I've seen some O.s not molt for 6 months. Also, if the animal has lost its raptorial appendages, it will decrease the molt interval.


As for how long it

This kinda sux for me. I am in need of doing a water change and my mantis is really close to molting. Anytime ive walked by the tank i took a short glance and he's been on his back all day not moving so clearly he is close. Can cutting the lights for a day speed up his molt? Or make it easier on him?:uhoh2:

Gonodactylus 07/21/2011 02:42 PM

This doesn't sound good to me. Stomatopods do not usually lie around on their backs for days prior to molting. With a healthy molt, you typically see increases in digging and aggression a few days prior to molting and the last day or two they can't strike, but not the behavior you describe. If it were me, I would tend to the tank with a partial water change being careful not to stir things up and matching the salinities between the old and new water.


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