B albiceps sling looking thinner, not eating

[remington]

I got a 1/2 inch B albiceps sling roughly three weeks ago. I keep it in a top ventilated 50 dram vial filled halfway with sub. It has a hide, moss, and a water dish. Half the sub is kept lightly moist. I see it moving around sometimes, just yesterday I caught it grooming near the water dish.
However, it has not eaten at all, and its abdomen is starting to look smaller and more oval shaped which is worrying me. I have been offering it prekilled and halved mealworms of varying sizes 1-2 times a week, and it has not shown interest even once. I have left the worm overnight as well as moved it slightly with tongs to try and entice the sling. No dice. My other tarantula is a bigger B hamorii sling, and it rarely refuses food unless it's in premolt. This extended fast is something I have never encountered before outside of obvious premolt. Included is a photo of the sling I took yesterday, as well as the enclosure (the paper on top has holes punched through it, it is blocking much larger ventilation holes I was worried the sling could escape through). Is an abdomen this size and refusal to eat a cause for concern?

 

[Blackdog]

I got a 1/2 inch B albiceps sling roughly three weeks ago. I keep it in a top ventilated 50 dram vial filled halfway with sub. It has a hide, moss, and a water dish. Half the sub is kept lightly moist. I see it moving around sometimes, just yesterday I caught it grooming near the water dish.
However, it has not eaten at all, and its abdomen is starting to look smaller and more oval shaped which is worrying me. I have been offering it prekilled and halved mealworms of varying sizes 1-2 times a week, and it has not shown interest even once. I have left the worm overnight as well as moved it slightly with tongs to try and entice the sling. No dice. My other tarantula is a bigger B hamorii sling, and it rarely refuses food unless it's in premolt. This extended fast is something I have never encountered before outside of obvious premolt. Included is a photo of the sling I took yesterday, as well as the enclosure (the paper on top has holes punched through it, it is blocking much larger ventilation holes I was worried the sling could escape through). Is an abdomen this size and refusal to eat a cause for concern?

Maybe try pre-killed pin heads crickets

 

[Not Savsonite]

As long as it has access to water and moist substrate not much you can do.
Brachypelma genus is known for refusing food for long periods.

 

[New2T’s]

Personally, I would add more vent holes. I always put vent holes in lids and enclosure. I use dram vials as well. I just think cross ventilation for all species is best.

Cute little Albiceps

 

[Arachnoclown]

Abdomen is larger then the carapace, looks fine to me. Keep offering prekilled food to scavenge on. Place tape on the inside of the lid and add new vent holes.