Insect and Spider Identification: Odd Insect/Animal found near Jim Thorpe rill, 1 by Wallyobass

Wallyobass wrote:
" it had a tail in the soil
he tried to dig it up but it was in pretty far in the soil.
so much so that a slight digging around, showed that it was more than a few inches in the ground.
It apparently stood up-right and was, with its abdomen and head was moving back and forth in a singular motion.
It never fully revealed itself, keeping it's tail securely fashioned in the ground "

phone conversation from my brother Christopher, who took the photos