The Proof is in the Pouch: Tealliocaris is a Peracarid

Tealliocarid eumalacostracans, known from Late Devonian-Carboniferous marine, non-marine, and estuarine strata of North America, continental Europe, and the United Kingdom, are here transferred from Eucarida: Decapoda back to Peracarida: Pygocephalomorpha. Species included in Tealliocaris exhibit a suite of peracaridan and pygocephalomorphan synapomorphies, including the presence of an oostegite marsupium in females, a distinct terminal telson lobe, and a pair of lateral telson lobes. Purported decapodan characters, e.g. complete fusion of the carapace and thoracic tergites, and the presence of only five pereiopods, in Tealliocaris seem to be poorly supported. A phylogenetic analysis included herein fully supports inclusion of Tealliocaris in Peracarida and in Pygocephalomorpha.