ABSTRACT
Recent revisions in callianassid subfamilies and genera are questionable and appear to be incongruous with relationships evident in morphologically based phylogenetic reconstructions. We generated molecular phylogenetic trees for the closely related families Callianassidae and Ctenochelidae as well as for outgroup representatives of the family Axiidae. Fragments of the 16S and 12S rDNA mitochondrial genes were sequenced for a total of 46 species, representing 18 genera of Callianassidae, two genera of Ctenochelidae, and five genera of Axiidae. Of approximately 1000 potential mitochondrial basepair characters, 903 were used in final alignments. Resolution in our phylogenetic tree was limited at some basal nodes of the topology, as might be expected with the genes chosen for this analysis. Callianassinae formed a well-supported monophyletic group, but Cheraminae was included within it. Support was found for continued recognition of many separate genera in this group and for the naming of additional ones, as opposed to their wholesale reassignment to the clearly separated genus Callianassa. Groupings within Callichirinae were not well resolved, though the subfamily appears to be paraphyletic at low support values. Genera of this group were monophyletic except for Sergio, which is paraphyletic and of questioned validity. Eucalliacinae appears to be paraphyletic at low to medium support, suggesting that the genus Calliaxina may share common lineage with the Ctenochelidae.
