Molecular phylogeny of Diabrotica beetles (Coleoptera : Chrysomelidae) inferred from analysis of combined mitochondrial and nuclear DNA sequences

The phylogenetic relationships of thirteen Diabrotica (representing virgife ra and fucata species groups) and two outgroup Acalymma beetle species (Col eoptera: Chrysomelidae) were inferred from the phylogenetic analysis of a c ombined data set of 1323 bp of mitochondrial DNA (mtDNA) cytochrome oxidase subunit 1 (COI) and the entire second internal transcribed spacer region ( ITS-2) of nuclear ribosomal DNA of 362 characters. Species investigated wer e D. adelpha, D. balteata, D. barber!, D. cristata, D. lemniscata, D. longi cornis, D. porracea, D. speciosa, D. undecimpunctata howardi, D. u. undecim punctata, D. virgifera virgifera, D. v. zeae, D. viridula, and outgroup A. blandulum and A. vittatum. Maximum parsimony (MP), minimum evolution (ME), and maximum likelihood (ML) analyses of combined COI and ITS-2 sequences cl early place species into their traditional morphological species groups wit h MP and ME analyses resulting in identical topologies. Results generally c onfer with a prior work based on allozyme data, but within the virgifera sp ecies group, D. barberi and D. longicornis strongly resolve as sister taxa as well as monophyletic with the neotropical species, D. viridula, D. crist ata and D. lemniscata also resolve as sister taxa. Both relationships are n ot in congruence with the prior allozyme-based hypothesis. Within the fucat a species group, D. speciosa and D. balteata resolve as sister taxa. Result s also strongly supported the D. virgifera and D. undecimpunctata subspecie s complexes. Our proposed phylogeny provides some insight into current hypo theses regarding distribution status and evolution of various life history traits for Diabrotica.