Acheronauta is a genus of extinct vermiform arthropod that lived in the early Silurian (Telychian-Sheinwoodian stages) Waukesha biota fossil site in southeast Wisconsin. This arthropod was first discovered alongside the biota in 1985, but wasn't fully described until October 2022. This creature was recognized and described as a possible early mandibulate (the grouping of arthropods including crustaceans and hexapods). This description is very important as much of the fauna of the biota remain undescribed, and it's discovery has allowed for paleontologists to get a better grasp of the diversity of the arthropod fauna at the site. Multiple phylogenetic analyses were preformed, and it seems that this arthropod forms a previously undiscovered clade with the Devonian stem-arthropod Captopodus,