Also, there are many varieties of lice. Check the bases of the feathers around your hens vent area and look for clumps of hard white lice eggs and any crawling adults
Some lice is clear and pale yellow/white and others can look brown and dark colored.
Just got a response from the entomologist who, unfortunately, cannot make an ID based on those photos. She said the pics were too unclear and too small. So.....
Again, I suspect a grain beetle, but they wouldn't be biting the hens I don't think. The search continues.
Hmmm...
They favor grain beetles. There are several kinds of grain beetles. Having those 3 sets of legs on the thorax identifies them as beetles. I have sent the description and your photos to an entomologist and should receive an email response later today. Love a challenge and a learning...