We are using DNA sequence data to get new insight into the phylogenetic relationships of the Siphonaptera. Thus far we have generated preliminary data for 18S rDNA, 28S rDNA, Elongation Factor 1-alpha, and Cytochrome B. These data are overall congruent and suggest that many flea families as currently constituted appear to be paraphyletic assemblages. This is especially true of the Ctenophthalmidae which has historically been a grab-bag of taxa. As we generate more data and have a better sampling of taxa, we should produce more robust topologies.
Parsimony analysis with all positions weighted equally and gaps treated as missing produced 16 trees, the strict consensus of which is given below. These data strongly support Siphonaptera as monophyletic, Boreidae as its sister taxon, and Nannochoristidae as the most basal of the mecopteran lineages. Ceratophyllidae is monophyletic and relatively well supported, as is Neopsyllinae. Leptopsyllidae is paraphyletic with Opthalmopsylla basal to Ceratophyllidae as seen with COII. Ceratophylloidea is monophyletic and the bat fleas (Ischnopsyllidae) are sister group to the other two leptopsyllids. Pulicidae sensu stricto is monophyletic, Tunga is basal to Rhopalopsyllidae + Stenoponia, and Rhopalopsyllidae is monophyletic.
Preliminary Phylogeny of Siphonaptera Based on 18S rDNA *
* This topology, or any description of this topology, cannot be reproduced, referenced, or used in any way without express permission from Michael Whiting. This topology is only preliminary and will certainly change as additional taxa and/or characters are added to the analysis.