This a ventral view of the head of a Box Elder Bug Boisea trivittata
152 images in Zerene Stacker. The structure running down the middle is the "beak" folded into its groove.
All I have left in my bottled insects are some flies and a couple of Bombas, all of which are too big fro microscopy, so its time to dust off the stacking rig with the bellows and 63mm EL-Nikkor.
Images made through a microscope. All subject types.