Instars

[Rookie]

Hey all,
I must admit, that over the months I've been on this forum, I have learned more about Tarantulas than I thought possible. But, there's one thing I still don't understan: the instar system (sounds like something in a modern car). How does it work? How do I know what instar Peso is in right now? This is associated with s'lings only, right?
Please help me out. Any referring sites along with an explanation would be great.
Paul

 

[looseyfur]

Peso is in the "superstar" instar.

heh

Actually he seems too big judging from the pic to be first or second instar, other then that he would be sub-adult I suppose.


10053yfur

E.:}

 

[conipto]

Instar means the same thing as molt. For example, first instar is Egg with leg stage (I THINK) and then from there it's second, third, etc.. Then Ultimate instar, for Males is the adulthood molt. Penultimate is the one before that, and Postultimate is the rare one that occasionally occurs after.

Bill

 

[arachnopunks]

Originally posted by conipto
...Postultimate is the rare one that occasionally occurs after.

Bill

Unless you are Joy......she always gets males that make it though the post-ultimate stage. I wish I knew her secret.

 

[Joy]

Originally posted by arachnopunks
Unless you are Joy......she always gets males that make it though the post-ultimate stage. I wish I knew her secret.

Oh, I wish they all did! But I do feel lucky to have 2 that survived it.

Rookie, my understanding is that you start with the egg (embryo) which then develops into an egg-with-legs (post-embryo), which then molts into a 1st instar. Instar might thus be described as the stage between molts.

Joy

 

[Rookie]

Hey all,
Hmm..curious. Okay, I'm learning. But, how can I figure out what instar Peso is in?
Paul

 

[ArachnoJoost]

Originally posted by Rookie
Hey all,
Hmm..curious. Okay, I'm learning. But, how can I figure out what instar Peso is in?
Paul

All you have to know for that is how many times Peso molted, it's that simple (and yet that difficult...). As stated before, I think that when they become spiderlings (after the nymph II stage) they are 1st instar. So count the amount of times he has molted since becoming a spiderling and you know what instar he/she is. This is very difficult since (almost) no breeder gives accurate molting records with sold spiders (this would be too much work I think). If you have someone with a pulchra of about the same size as you who does know what instar his/her specimen is, you can try to figure out which instar Peso is...
greetz,
Joost

 

[Code Monkey]

Originally posted by Rookie
Hey all,
Hmm..curious. Okay, I'm learning. But, how can I figure out what instar Peso is in?
Paul

Unless you've been tracking him from the time he emerged from the sac, you can't. Some inverts have very specific milestones, e.g. sexual maturity on the 7th instar, but Ts don't follow such a fixed plan.