I keep seeing these birds recently. This is one in particular that I saw. ID suggested by friends that I consulted. It flew off too quickly to get a photo, but I sketched what I remembered on my phone immediately after I saw it.

Dark-brownish-grayish bird with a rusty-colored belly, a yellow beak, and some light gray streaks around the ends of the wings.

I was driving north on Highway 26, appx 5 miles South of New Augusta around 7pm when I found very recently killed specimen in center of the road. It had not even had enough time to have gone into Rigamortus.

Unfortunately, I believe this was intentionally killed as the rattles had been cut off. Head obviously beaten in.