The leafhopper tribe Proconiini (subfamily Cicadellinae, referred to as sharpshooters) comprises approximately 350 species in 56 genera restricted to the New World. Sharpshooters are among the most diverse herbivores in tropical rainforests and are vectors of the bacterium Xylella fastidiosa causing diseases of over 20 economically important plants. Proconiine females from 14 genera coat their eggs with microscopic lipoproteic particles (brochosomes) produced by the Malpighian tubules, in a behavior called egg-powdering (EP). Associated with this behavior are unique, sexually dimorphic, structural modifications of the brochosomes, forewings, and hindlegs of these sharpshooters. The objective of this work is to estimate the phylogeny of the tribe Proconiini and elucidate the evolution of the traits associated with EP. A preliminary dataset included approximately 20 outgroup taxa (Cicadellini and Phereurhininae) and 60 species belonging to 36 genera of Proconiini. Characters examined included partial sequences of the mitochondrial genes COI, COII, 12S and 16S rDNA, and ca. 60 external morphological characters. Maximum parsimony and likelihood analyses were performed for various combined datasets. The monophyly of Proconiini was not consistently recovered, but most clades not supporting this relationship received low statistical support. Proconiini appears to be divided into two main lineages and just one of them includes genera showing EP characteristics. Present results suggest a concerted origin of EP-associated traits at the base of this lineage and multiple secondary losses, rather than a stepwise temporal acquisition of the modifications.
Species 1: Homoptera Cicadellidae Homalodisca coagulata (glassy-winged sharpshooter)
Species 2: Homoptera Cicadellidae Homalodisca lacerta (smoketree sharpshooter)
Keywords: Phylogeny
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