Submitted to: Journal of Molecular Evolution
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/20/2000
Publication Date: N/A
Interpretive Summary: Leafmining flies in the family Agromyzidae are responsible for millions of dollars of losses to U.S. farmers and horticulturists each year. This paper provides the first phylogentic analysis of relationships among the leafmining flies that attack both cultivated and natural hollies. Using DNA sequence data we determine species limits and estimate relationships. We also identify four previously unknown species and discuss the ecology and feeding patterns of all the species that feed on hollies. This information will be of interest to ecologists and evolutionary biologists as well as to horticulturists and those interested in hollies.
Technical Abstract: We conducted a molecular phylogentic analysis to determine relationships and investigated character evolution in the Phytomyza ilicis group of leafmining flies on hollies (Aquifoliaceae: Ilex). We sequenced 2217 bp of the mitochondrial cytochrome oxidas I and II genes for all known holly leafminers as well as for several undescribed members of this group. Maximum parsimony analysis of our sequence data indicates that these leafminers form a monophyletic group with the inclusion of an undescribed leafminer which feeds on the distantly related plant Gelsemium sempevirens (Loganiaceae). Species boundaries of previously known as well as undescribed holly leafmining species were confirmed with the molecular data. Optimization of variable ecological and morphological characters onto the most parsimonious phylogeny suggests that these traits are evolutionarily labile, requiring multiple instances of convergence and/or reversal to explain their evolutionary history. Speciation in holly leafminers appears to involve colonization of new hosts rather than cospeciation as the hosts diverge. Monophagy is the most common feeding pattern in holly leafminers, and more generalized feeding is inferred to have evolved at least three separate times, possibly as a prelude to speciation.