Motoro pup is here

I went to the bathroom at 8 am, checked on my fish and went back to bed till 10. At 8 the female was still preggo. At 10, I turned on the lights and she is skinny and there is 1 pup on the back wall. I have the pup divided in the 500 gallon. The pup has about a third of the tank. He/she seems to be stabilized, moving around a little. I spooked it putting the divider in and it covered himself with the sand. I am off to the lfs to get some bloodworms. Also, I used to have africans so I have tons of mysis. Can I feed this rather then bloodworms? The pup has a nice long tail and looks to be a healthy size. I fed the mother very well while she was pregnant.

Pics later today

I don't see a yolk sac. Where is it located? He moved to a new part of the tank and buried himself in the sand again.

Ill take a picture when he/she comes out of the sand

Best I could get for now

I took the ray out in a transparent container to sex the motoro. Its a female. . I am surprised how active she is. Moving around lots on the bottom,checking out the tank.She likes to swim to the top of the tank