And what are these?

Not the obvious plants in the perimeter of the frame, but the roundish things.

 

Lithops sp?

 

Dried-up windblown flower petals?

 

Turtle eggs?
Or those of some other reptile---snake, crocodile, or the elusive gharial?

 

Kind of far away to tell.

 

One of the guessers is in the right kingdom...

 

Some creature's scales?

 

That's very much in the right ballpark.

 

Fish scales are shiny like these.

 

I find fish rather bony.

 

Guessing that the fact the photo was taken in what appears to be a seasonally flooded spot is important?

Lizards are less 'bony'....though more chewy.

 

Seasonally flooded is very important.

 

Armadillo scutes? [Edited]Or maybe the Armadillo's epidermal scales, though your clue would point more to the bony scutes. And I see that they can swim and remain under water for up to six minutes, so like bony fish.

 

I did not know that about armadillos. But these are not that -- much smaller organisms.

 

Frog?

 

Nope, not frogs -- though it is something frogs will eat (salamanders, ducks, shorebirds and wading birds, too)

 

Crab?

 

Getting really close now! In the right zoological subphylum!

 

Crayfish?
Pacifastacus?

 

Opercula from some species of Gastropod?

 

It is related to crayfish, same subphylum.

 

Maybe Cladocera (water fleas) or Ostracods? Adapted for living in temporary pools?

 

Close enough, since you have the right idea. Clam shrimp:

 

Thanks for the link. I love how they're strong swimmers, but don't really bother going anywhere and they use their gills to get the food to come to them. My kind of lazy. The video was fun.