beetle id: larvae in dogs poop

[toehead11183]

I pick up dog poop 2-3 times a week, the older poop always has maggots and little black beetle larvae with a light colored spot. i havent found any adults and havent been able to ID online.
They are slightly smaller than common fly maggots, all black with a light colored segment. crawl off as soon as you disturb the poop. Ive googled the larvae of all the common bugs in the area without anything. These larvae are in every turd that stays out there more than a few days and they consume the pile very quickly. any clues bug people? i live in west tennessee

 

[noelsfishland]

you sure the dogs do not have worms? very common in dogs kept outside If not on heart worm medication

 

[toehead11183]

no worms, these are BEETLE larvae. with legs, eyes, etc. intestinal worms arent beetles