RESUMO
Species of Marphysa belonging to the Aenea-group have compound falcigers as the subacicular chaetae along the entire body. Around 30 species belong to this group, among these, two have originally been described based on Australian specimens, M. bifurcata and M. sessilobranchiata. Here, we redescribe both species based on type and non-type material and describe a species new to science, M. pseudosessiloa n. sp., including intraspecific variation. Informative features for the identification of these species are relative length of prostomial appendages in relation to prostomium, shape of notopodial cirri, left MxIV plate, left and right MxIV attachment lamellae and placement of branchial stem. A taxonomic key to species of Marphysa currently reported from Australia is also provided.