Picture of Shell Disease in O. scyllarus

[Gonodactylus]

I've been asked several times to submit a photo of shell disease in a Peacock Mantis Shrimp (Odontodactylus scyllarus). Today I pulled out this male to send off for some research on its eyes and noticed that it had early stages of shell disease on its abdomenal tergites. There are three patches forming. In a couple of months, without treatment, these would turn orangish brown and eventually the cuticle would begin to be penetrated. At this stage the disease is still treatable with low nitrate levels and excellent water quality, low light and good nutrition. I deep, dark burrow is almost essential. UV sterilization also helps.

Roy

 

[Msby12]

thanks Dr. Cadwell, unfortunately, i think i have seen these spots on my o. scyllarus

 

[Janina]

Here are a couple more pics of shell disease on my male O.S.

The area in the white circle is an open lesion according to Dr. Roy but you can also see all the other orange grey spots as well.

 

[pinobutter]

how easily spread is this shell disease? and can it be spread to another type of mantis for example say i got a peacock with shell disease and a wennerae in the same tank seperated by a divider will the wennerae catch it too??

 

[Gonodactylus]

The quick answer is that we don't know very much about shell disease. O. scyllarus are by fare the most likely to get it, particularly large males. Large male G. ternatensis are also prone to getting it. I have seen G. chiragra with it, but never a Neogonodactlylus. Hemisquilla gets a similar fungal disease, but I doubt that it is the same.

Roy

 

[pinobutter]

thanx Dr. Roy ahh would you happen to know where i can get some books or stuff to read up on about illnesses or diseases that affects mantis shrimps?

 

[pinobutter]

oops i forgot to ask so a neogonodactylus is safe then far as you know but other gondactylus are vulnerable then ? cause i just picked up a smithi not long ago and there was a peacock there as well looking like it had shell disease sharing the same filteration and water along with other inverts will my smithi end up with shell disease now too?

 

[Gonodactylus]

I don't know of a single paper or book that discusses diseases in stomatopods.

I can't remember seeing a G. smithii with shell disease. The only species that seem prone to it are O. scyllaurs, Hemisquilla, G. ternatensis and G. chiragra. You might notice that these are the four largest smashers.

Roy

 

[pinobutter]

thanx Dr. Roy for the info

 

[bump321]

So the O. scyllaurs girls dont get it as often ? Do you now why the males get this more ?

 

[bump321]

You say a deep, dark burrow is almost essential.

How deep would it need to be ?

I have a OS & she is right at 4 inches & is in a 20g long. How deep of a sand bed is needed if this ever happens to her ?

What causes this to happen to them ? You said yours had it underneath it. So is there a good way to ck them over so we can catch this early on & how often do you ck for it ?

I wouldn't want to try & pick Libby up to ck out her tummy. How do you handle your shrimp when need be ?

 

[Gonodactylus]

First, shell disease nearly always starts on the back of the animal - carapace and tergites. It is rare to find it on the vertral sternites. I'm not sure why this is. It could relate to light, but more likely it has to do with the ability of the animal to thoroughly clean its cuticle. It is more difficult for them to reach their back and effectively scrub the surface. Another possibility is that the dorsal surfaces may be more subject to damage - scratches, wounds from fighting, etc.

As to why male O. scyllarus and G. ternatensis are more prone to get the disease, I can only speculate. Large males molt very infrequently, so there is more time for the disease to get a foothold. Large males also spend more time out and about looking for females.

Roy

 

[bump321]

Thank you Roy. I will keep a look out on my girl when she is out running around.