Archisymplectes is an enigmatic worm from the Essex portion of the Mazon Creek Deposit. It is always preserved as just a color difference within the concretion. Specimens are nondescript preserving a basic worm shaped body without segmentation or any other obvious structures. Some specimens preserve an everted proboscis. This proboscis is what led the original author to classify it as a Nemertean or ribbon worm. There are no clear Nemerteans known in the fossil record ho