Late Cretaceous (Maastrichtian)
Hell Creek Formation
Wibaux County MT, USA
Very weird 17mm insect larva preserved in ironstone.

Insect.

Here’s a strange fossil you don’t hear about from the Hell Creek Formation, a unit famous for preserving the remains of the last dinosaurs on earth.  There is almost nothing published on the insects from the Hell Creek largely due to the fact they have been discovered only recently and they tend to be trace fossils.

An example of unusual preservation of an insect.