Black dot on the abdomen a few weeks after molting?

[Fiffle]

I fed my B Smithi Juvie yesterday for the first time since it molt and all went well. I took the bolis out and noticed it had a black spot on it's abdomen like a pre molt sign but it just molted. Is it a pre molt spot or some sort of marking?

 

[Chicken Farmer]

my slings get spots like that. I think it is a sign of pre-molt. soemthing like that...

 

[Fiffle]

Yeah but for a 2 inch juvie I don't think they go into pre-molt a week or two after they molt. I could be wrong though, this is in fact my first T.

 

[Formerphobe]

Can you post a picture?

 

[Fiffle]

The picture's kinda blurry but you can see the black spot on it's abdomen.

 

[jdl]

With Brachypelma and Aphonopelma the spiderlings have that black spot on their abdomen. When they are first born the black dot is smaller and with each molt the spot gets bigger until the entire abdomen is black. This is normal, and not a sign of molting.

 

[Fiffle]

So when it does come time for pre-molt, I wouldn't really be able to tell by the spot on it's abdomen? Well with the exception of the last molt because it did have a small black dot on it's abdomen before it entered pre-molt but it wasn't as noticeable as this one.

 

[MarkmD]

I see no spot, I do see a line dark line, but that's normal as a T eats the abdomen expans.

 

[Curious jay]

Are you referring to the urticating hair patch? Otherwise.... I see no black spot.

 

[Formerphobe]

The black line leading from the pedicel to the urticating hair patch is part of the heart. The black 'spot' encompasses the urticating hair patch. If it kicks hairs, it may develop a bald patch that will act as a 'window' to see if the abdomen is turning dark in pre-molt. Whether it kicks hairs or not, the entire abdomen will turn dark, then black, to the point that you won't be able to distinguish where the heart is. All normal.

---------- Post added 12-08-2012 at 05:24 PM ----------

With each successive molt, the abdomen becomes more heavily setaed until neither the black 'spot' nor the heart are as noticeable.
In the following pics you can see both the urticating hair patches and the cross-pieces of the hearts.

Brachypelma albiceps

Aphonopelma burica

 

[jdl]

When the spider is premolt with that black spot the area under the spot will blacken up, but if you look closely you will be able to tell that the blackening under the skin. As some people have posted, the spot is urticating hairs, and often they will kick off the hairs and the area will will look like the rest of the abdomen. At this point it will be easy to see when it is darkening up for the pre molt.