While recognizing that addition of further taxa may alter some of the groupings obtained, the present analysis, based solely on spermatozoal and spermatophore evidence, indicates that, the Anomura and two of its constituent superfamilies, the Paguroidea and Galatheoidea, are not monophyletic assemblages. The infraorders Astacidea and Brachyura appear to be paraphyletic to most of the Anomura. The Anomura (with the possible exception of Lomis) share the unique synapomorphy of having microtubular arms of cytoplasmic origin. The superfamily Thalassinoidea is not a monophyletic group of taxa (even when they are designated as the outgroup). The only monophyletic anomuran families are the Coenobitidae and Porcellanidae, the Diogenidae, Paguridae, Chirostylidae, and Galatheidae appearing to be paraphyletic. The paguroid families Paguridae and Parapaguridae form a monophyletic clade with the exception of Porcellanopagurus. The two representatives in the family Chirostylidae (Eumunida and Uroptychus) do not group with the other investigated galatheoids. The hippoid Hippa forms the sister group to the remainder of the anomuran taxa (with the exception of Lomis). Lomis occurs as a separate (basal) sister taxon to the remainder of the Anomura and the Astacidea and Brachyura.