black spot on abdomen...

[Yve]

I've been checking in on my mex. redknee twice a day since I picked it up 2 weeks ago. It ate once just over a week ago and has been hiding in a burrow for almost a week now. Today I looked at it and its abdomen has a black spot on the back.....does this mean its going to molt?...I've heard they darken when they molt but haven't seen a pic. of what that looks like.

[Pixie]

Yes, I too would guess that it is getting ready to molt.

The abdomen gets dark, almost black when the hairs have grown in "under" it's current skin.

If you could post a pic, that would be great!

Pixie

P.S. Congrats on your new red knee, they're awesome :D

[Yve]

thanks Pixie, I can't wait for it to grow up! its so tiny right now (about 1/2") looks like something I'd find in a garden up here!lol unfortunately the s'ling is in a position that I cannot take a clear picture of it. I'm waiting at this point to see if it flips upside down.

[Dragoon]

OK, someone correct me if I'm wrong, but ....

I have 4 different Brachypelma species, 3 of them slings, and all have a black dot on their butts. Freshly molted or not. They are all molting once a month, and when freshly molted, are pink skinned, except for the dot. I have theorized that that is the site of beginning to make pigment, and eventually the whole spider will be colored as they mature.
I know they will molt soon when they have amassed a giant butt, and their appetite wanes.
D.

[Tarcan]

Absolutly Dragoon...

Yve,

When Brachypelma spp. slings start to grow (well many different species, this is valid for the extremely small slings that usually hatch whitish and bald, like Lasiodora spp., Acantoscurria spp. ...talking hatchlings here), they start having a little black spot of setae on the opisthosoma... that does not mean they will be molting... if you see only a spot...

It is when the abdomen turns completely darker that it is getting ready for a molt... but in the case of slings, "darker" is the key word and not necessarly black, do not be fooled...

In any cases, finding if your sling is in pre-molt is pretty easy, you will get used to it when you get a little more experience with it (but I understand it is stressful for the moment, we all have been thorugh this stress!)... if it does not pounce on the food almost right away, it is not hungry... if it does that a few days in a row... do not bother feeding it until it molts back... it is most probably in pre-molt...

Monitor the size of the opisthosoma... because it happens that we are wrong...if it starts loosing a little wait... then you took the wrong guess, it might be still hungry... so try another meal...

I hope this helps, and good luck with your animal

Martin

[Yve]

thanks Tarcan, that gives me a better idea atleast what to look for.....the s'ling has been in its burrow for almost a week now and hasn't eaten anything since he's burrowed. The spot is black and clearly defined. Right on the back..looks like someone put a blob of ink in one spot. I do check on it a couple times a day.... to see if there are any changes in the posture, shape and colour. Every few days I try to feed it. Do you think the s'ling is stressed by this if preparing to molt? I didn't think he would be because the cricket can't get to him...the burrow is closed off. I just didn't want to make the mistake of assuming he's in molt and not providing him with food just incase he's not.

[Tarcan]

Yve,

If it's burrow is closed that is the best indication that the spider does not want to be disturbed... with Asian species that burrow a lot, somtimes it is the only way of telling if you need to feed or not since you never see the spider itself...

With a Brachypelma spp. sling such as B. smithi, do not worry too much about the feeding (not having enough food)... if the opisthosoma is nice and plump, even a sling of this species could go for two weeks without eating...

Good luck with your spiderling

Martin

[Dragoon]

Ok, I've been thinking about this one for a bit...

If the black spot is the presence of setae (hair), then what covers the rest of the T? a shell? is it really naked?
And what about the purpose of the setae...isn't it to pick up air currents and vibrations and stuff? So this means the pink bald babies are really helpless?

Hatchling avics have hair. And they are bigger. Maybe this is a common difference between arboreal and terrestrial spiders. I think then, that the majority of the terrestrials must have large egg counts, to make up for the tiny helpless babies they produce....am I on the right track?
Just rambling...
D.

[Tarcan]

Not all terrestrial species have large egg counts... T. blondi, Xenesthis spp., etc. They have clutches of 60 to 100 (sometimes less, sometimes more). And the hatchlings are huge... and hairy

Babies are always helpless anyway so do not worry too much about them!LOL I believe they can still feel vibration from the ground though...

For your question about the setae, go to page 19, 35-36 of Mr. Schultz book, you will find plenty of info and a few other pages also... Verdez has also a nice explanation of teh different types of urticating setae...

Martin

[Dragoon]

Thank you, I have not read the whole book yet...I kinda skipped the scientific stuff at the beginning, now I will go back and read it!
Take care
D.

[Yve]

well I think the time has come.......the spiders legs are back and its on its side. does the molting process vary between species and the age of the spider? Its been hiding for over a week hasn't eaten in 2 weeks and has finally gone into the "oh my god my spiders dead" postition..:) Another thing that I'm wondering about is how temperature affects the molting process? Does it speed it up or slow it down?