Larva missing limbs.

[KJ_29]

Hey guys,
It's just over a month since my first C.Orientalis eggs hatched, and the larvae seem to be doing well.
I've noticed one of the larvae is missing its front two legs (which I'm almost totally certain had developed initially); more precisely, they appear to be significantly reduced in size.
The rest of the larvae, including the limbless one, are just beginning to develop hind legs.
I've read a bit on limb regeneration in adult salamanders, but I'm fairly ignorant when it comes down to same process amongst larvae.
I'm not sure what the cause is. It seems unlikely that they've been bitten off due to overcrowding, and though I'm quite meticulous regarding water changes/quality, I suspect infection could be a likely cause.
I've around 40 larvae, but only one case like this. The larva is currently in a tub on its own.
Any advice or guidance, or accounts of similar experiences, that anyone could offer would be very much appreciated.
Karl
(I'll try and get some photos up soon)

 

[SludgeMunkey]

Sounds like nibbling by conspecifics to me.

Cynops sp. do best in very heavily planted rearing tanks, that is, ones lots of java moss or the like. Another cause of this is population density.

Too many larva in one tank, and they will nibble at each other inadvertently.

Cynops sp. will bite at just about anything that moves, so sometimes they inadvertently bite each other.

Good news is, the missing limbs will grow back on healthy larvae.


You have about 40 larvae in what volume of water?

 

[KJ_29]

I've got 41 spread across 7 tubs (6 tubs of 6, and 1 tub of 5). The tubs measure roughly 24x24x10cm, with roughly 8-9cm depth of water.
As regards to plants, all I have at present are elodea and cabomba trimmings, which aren't particularly dense.
After hearing what you've just said, I'll probably look towards planted tanks, rather than my current set up.
Only one (although that's one more than I'd hope) has missing limbs, but if there's a chance this could happen more often as the larvae grow, I'll move them to larger set ups sooner rather than later.
Have you any specific recommendations now you know what set-up I'm using?
Thanks very much, I appreciate it.

 

[SludgeMunkey]

Sounds like you have the right idea, mate!

Only thing I would do different is I would add lots of plants. Lots and lots of plants. I suggest Java moss, as it sits on the bottom and grows through all levels. Gives lots of places to hide. It is also easy to remove and clean. Something I did with mine with great success was to sort out the larvae by size into their seperate tubs. Every few weeks I have to re sort them, but this keep s the big guys from hurting the smaller ones.

I wouldn't worry about your front legless larvae too much, they should regrow without issue. However, if you notice they are not regrowing (takes weeks), or their are absolutely no stumps, it may be wise to cull the little guy, so that he does not produce similarly deformed offspring. One with out any front legs will most likely not survive morphing. I am a bit new to Cynops, however I was shocked to see they hatch with front legs!

I know, I hate having to cull also. I had about nine runts in my current batch that just were not growing. Two months old, skinny as rails, and still only 2/3 of an inch long. Their brethren are nearing 3 inches and getting very close to morphing.

Reading and searching the forums, I found quite a bit on the whole process of rearing these guys. There are quite a few Cynops experts here, and they all have put a lot of information into the forums on the topic.

 

[KJ_29]

Brilliant, cheers. I'll seek out some Java moss then.
Hopefully culling won't be necessary; the limbless larva looks as developed as the others, so hopefully that's a sign that he's healthy enough to regrow his legs.
Thanks for the reassurance.
Yeah, there's certainly a wealth of info available on here; the writers of which, I'm beholden to, haha.
I'm pretty certain that a thread of yours, documenting the growth of larvae, is one I regurlarly refer to.

 

[SludgeMunkey]

Feel free to join in on that one! I am learning too! My area of expertise is more with axolotls, live foods and vivaria construction, so I feel the more of us that get together and compare notes as we raise these little guys up, the better off we all are. I think right now there is at least a dozen Caudata.org members worldwide that all have Cynops in various states of growth. Plus, I enjoy reading about how other folks do it. often I discover my "hillbilly husbandry" methods can be improved upon.

 

[KJ_29]

Good news, the larva's making considerable progress in regrowing its limbs. It's happening fairly quickly, and doesn't seem to have any significant effect on the larva's growth as a whole.
I'll have to make a contribution to one of threads dedicated to larval cynops. I've attached a picture to this thread (before I go about hiijacking someone else's) of some of my most developed so far. It's great watching them develop over time.

 

[Hardwarehank]

Sludgemonkey: Did you mean to say 3 inches or 3 cm? I hope you meant cm or my c.o. larvae are waaaaay behind. And it's good to hear that their limbs will grow back so early in development. I have a couple missing limbs as well that used to be there.

 

[Azhael]

Looking good Karl. Don´t worry about missing limbs, at this age they regrow them really quick. They can regrow them after metamorphosis too, but it takes longer.

It´s always good to see CB animals of the Cynops genus. Hope to see a first morph post in a couple of months hehe.

 

[KJ_29]

Cheers Azhael. Yeah, I've noticed an increase in the size of what was left of the legs; hopefully it won't be too much longer til they've fully regrown.
Haha, I can't wait for the first of the morphs either; it's all quite exciting.
Hank, hope you don't mind me answering, but for C. Orientalis, larvae won't reach three inches. My oldest, at around 1.5 months, are nearing 2cm; if that helps.

 

[SludgeMunkey]

Sludgemonkey: Did you mean to say 3 inches or 3 cm? I hope you meant cm or my c.o. larvae are waaaaay behind. And it's good to hear that their limbs will grow back so early in development. I have a couple missing limbs as well that used to be there.

Sorry about the confusion there, I forgot to switch to Metric...

I was referring to a fractional inch, 2/3rds or about 17mm.