Anyone ever seen these "stretch marks" (red marks) before?

[Mindibun]

I noticed these weird black lines on the underside of my G pulchripes' abdomen about a week before he molted. I couldn't figure out what they were but he was excessively girthy so I thought maybe "stretch marks" of some kind since he was so close to molt. He successfully molted the other day and I pulled the exo to sex him and noticed he had molted out of the "stretch marks." He is very fuzzy right now so I can't tell if they are still on him for sure, but it doesn't look like it. I soaked the exo in vodka and looked at it under the microscope. Nothing was moving (worms of some kind were my worst fear) and I just don't know what to make of it. Any ideas?

From the inside of the exo:

From the outside of the exo:

It looks like maybe he scratched his abdomen on something and it was a scab but he has nothing even remotely sharp in the enclosure. It's just cork bark that's absolutely COVERED in web, and eco earth.

 

[Keith B]

Never seen anything like that before. Stretch marks would seem unlikely though. Maybe drag marks? Did it have trouble keeping the girth elevated when walking around/pouncing at prey?

 

[CitizenNumber9]

What would concern me is that they seem to be deeper inside of the exo rather than outside.

 

[MrCrackerpants]

This is a new one for me. I am hoping someone has also seen this. Glad to hear your T is OK.

 

[Silberrücken]

True Spiders get this too. Case in point: Kukulcania hibernalis adult female







This female is due to molt very soon. I have no idea what caused her marks. I am hoping she molts out of it with no problems.

 

[Smokehound714]

looks more like lesions than stretch marks

 

[Scoolman]

I am thinking these are caused by feeding. The spider gets fat at an accelerated rate, and often gets much fatter than it would in the wild. This could cause the exo to tear, or stretch.

 

[Mindibun]

Now see, that true spider's marks look like scabs. On my T, they never looked like that. It just appeared as very thin (as in vein-thin) lines/marks that were not swollen or red. They just looked black and appeared to be under the skin. Very weird... But as I said, my T seems to have molted out of it so I hope your spider does as well. My T went off feed for several months before the molt, and as he didn't have the marks before-hand, and they developed only two weeks prior to the molt, I don't feel that it was caused by feeding. I just don't know... I'm at a loss.

 

[MrCrackerpants]

Now see, that true spider's marks look like scabs. On my T, they never looked like that. It just appeared as very thin (as in vein-thin) lines/marks that were not swollen or red. They just looked black and appeared to be under the skin. Very weird... But as I said, my T seems to have molted out of it so I hope your spider does as well. My T went off feed for several months before the molt, and as he didn't have the marks before-hand, and they developed only two weeks prior to the molt, I don't feel that it was caused by feeding. I just don't know... I'm at a loss.

Weird.....................................