Difference between 1 eggs with legs and 1 instar?

neubii18

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My female recently layed a sac(my first),amd when I pulled it,there are lots of healthy babies in there.My question is,are they eggs with legs or first instar?What's the differences between the two(visual differences)?I'll post pictures tomorrow if no one can describe the differences.Thanks!
 

Zman181

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I take it this little guy cannibalized a sibling while in the sac. I was wondering the same as far as the difference between eggs with legs and 1st instars.
 

Thegloryfades

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That picture is first instar I do believe. Eggs with legs will usually be just that immobile egg that have legs. I could be wrong and please correct me if so but that's my understanding
 

Philth

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Tarantulas first lay eggs like this...


Then depending on the species , 2 weeks to 4-6 weeks they look like this...eggs/embryos (Nhandu tripepii)


The next stage is "eggs w/ legs". or post embryo. They can move there legs a a little, but cant walk around just yet.( Theraphosa blondi )


The next molt is first instar. They are now mobile and can walk around a bit. Some species will feed at this stage and might cannibalize on siblings, but for the most part do not need to be fed yet, (Phlogius sp."PQ113")


The 2nd instar molt is when most spiders are seperated and sold. At this point they have molted into hairy, fast , self feeding spiders. There is always exceptions though as some Poeciotheria have an "extra" stage and ( formasa , metallica) and wont have to feed until 3rd instar.
(Psalmopoeus cambridgei )


Later, Tom
 

Hobo

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Please read this post.
Very detailed explanation. Be sure to look at the pics. What most of us call 2nd instar might actually be 3rd instar for a lot of species including G. rosea.
 

Philth

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Please read this post.
Very detailed explanation. Be sure to look at the pics. What most of us call 2nd instar might actually be 3rd instar for a lot of species including G. rosea.
Briefly skimmed through the long post but I dissagree with the pics that Stan provided in this link. The pictures he has labeled as postembryo and 1st Instar are at the same stage.

Later, Tom
 

Hobo

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Briefly skimmed through the long post but I dissagree with the pics that Stan provided in this link. The pictures he has labeled as postembryo and 1st Instar are at the same stage.

Later, Tom
That's why I was (and still am) so confused, and that's what I thought before he replied (you can see my replies in that thread) and we exchanged a few emails.

I watched the slings (perezmilesi and avics) I've hatched out, and they never molted into another "post embryo" like stage. With my avics (though they didn't make it to second instar), I had them as eggs, they hatched into eggs with legs, and the next molt was into what most of us would call first instar. I am SURE they did not molt in between, because I only had 3 survivors, and would have noticed cast off skin.

But then again, he has years of experience and credentials to back up his post, so I don't know what to think.

At the very least, I know at what stage they start to feed at (and some that do so an instar later) at least, regardless of what that instar is labeled as:D
 

Protectyaaaneck

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Briefly skimmed through the long post but I dissagree with the pics that Stan provided in this link. The pictures he has labeled as postembryo and 1st Instar are at the same stage.

Later, Tom
I was thinking the same thing. I don't see any difference between the two other than the fact that the picture he has labeled as 1st instar are just darker postembryos.
 

Hobo

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I was thinking the same thing. I don't see any difference between the two other than the fact that the picture he has labeled as 1st instar are just darker postembryos.
In the second picture, the prosoma, legs, and chelicerae appear to be larger/longer and more developed when compared to those in the first picture. The opithosoma, while still the same color, seem to have hair in the second picture that can't be seen or isn't present at all in the first. Finally, the sheds in the second picture clearly have legs on them, suggesting they molted from a form that already had legs.:confused:

The post is more convincing if you read through it, rather than just skimming it. He explains a lot of his reasoning.

It's still confusing for me though, when personal experience says something else.:?
 

Rue

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I'm very impressed by everyone's photos and the details displayed.

In Stan's photos...I see a difference...but maybe his post-embryo photo is a 'later' one and his first instar photo taken at an 'earlier' point of time? There is growth within each instar...

But yes, the differences in Tom's photos are more obvious.
 

billopelma

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Please read this post.
Very detailed explanation. Be sure to look at the pics. What most of us call 2nd instar might actually be 3rd instar for a lot of species including G. rosea.

I read through the whole post and the only explanation I can see is if G. rosea has the ‘extra’ instar like P. metallica and this is not applicable to most other species. I think some of his answers to the questions were a bit ambiguous and therefore confusing. I really hesitate to think someone with this level of experience could be that wrong but, like Hobo, I’ve had pretty direct experience clearly showing otherwise.

My most recent example is with a P platyomma sac I opened at the end of December, finding mostly viable postembryos but in a somewhat messy situation. Many had only partially emerged from the chorion with legs and carapace clear but chorion still partially wrapped around/clinging to the opisthosoma.

To really complicate things many were stuck together (mostly chorion to chorion) in clumps, looked like the eggs/chorions had been sticky and had then dried, adhering to each other in the process. I left them like this for a week or so with increased humidity and decided then that it would be worth the risk to separate them, as I was obviously concerned the first molt would be problematic in such a state. Most separated with relative ease but some chorions were difficult to remove so I left them to see if they would self-remedy, rather then chance damage to the postembryo while attempting the cleanup.

This is where things become applicable to this thread. The postembryo’s originally looked like the ones in Stans postembryo pic, pale pink/yellow and no discernable bristles. As time progressed, they started looking like the next pic with some darker color appearing and obvious bristles. I know they could not have molted at that stage because I had cleaned up all the debris when I pulled them apart from each other and also some were still partially encased in the chorion. I think it would be hard to molt cleanly with the chorion still present on the opisthosoma. There were no artifacts of any molt activity whatsoever.

They have since molted to first instar, where they’re mobile but in that between stage where they still don’t look like real T’s yet. It’s taking forever for them to hit 2nd instar and it’s driving me crazy waiting…


Bill
 

SC Tarantulas

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When they go from Eggs to "eggs with legs" the experts do not consider this a true molt (there is not a true exoskeleton at that stage). When they molt from the "eggs with legs" stage then this is considered the first true molt (1st instar) because they shed there first true exoskeleton.
 

neubii18

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So if they move,they are 1st instar?Because my A.Avic slings move.And they are all darkening quite a lot.That would mean they're about to turn to 2ed instar where they actually look like Ts,right?Thanks for everyone's help!
 

Philth

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So if they move,they are 1st instar?Because my A.Avic slings move.And they are all darkening quite a lot.That would mean they're about to turn to 2ed instar where they actually look like Ts,right?Thanks for everyone's help!
Post embryo /eggs with legs can move their legs a tiny bit. 1rst instar are mobile and can walk around. Post a pic of what you have, to know for sure.

Later, Tom
 

Big_nito

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Tom quick question. To avoid cannibalism, would it be advisable to separate 1st instars? I tried to leave 1st instars before and noticed that fewer made it to 2nd instar. I dont know if they were eating each other but I just saw dead ones... Now, I tried to separate my 1st instar slings already and I noticed that I have not yet lost any of them so far... I dont know if separating slings as young as 1st instar increases their survival rate...


Mike
 

Philth

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I dont worry to much about 1rst instar eating each other to much as it does happen, but not on a large scale. I feal that they are cannibalizing on weaker siblings that weren't going to make it anyways. Sometimes with faster old world slings I'll separate them at 1rst instar just because its easier to deal with them at this stage. Opening a container with a couple hundred 2nd instar H. maculata for example will usually result in spiderlings running all over the place.

I dont think separating them at an earlier instar would change the death toll, but its prob more related to the conditions the slings were kept in, and just the general health of the spiderlings from those particular eggsacs.

Later, Tom
 

Bosing

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Thank you Philth!

I take it that these are first instars and that I can still afford to let them stay together? C. darlingi babies...





 

Falk

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Just want to ad that Monocentropus balfouri also have that "extra" stage.
 

neubii18

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Sorry it took so long to get these pictures but...

Here are a couple pictures of my A.avicularia slings.Are they 1st instars or eggs with legs.They move their legs,and I think they move around a little,but I'm not 100% sure.What do you guys think?



 
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