Luciano Palmieri, PhD
Paracrias ceratophaga (Palmieri & Hansson), a Eulophidae wasp that feeds on Ceratopus larvae.
Fig species are keystone resource for several groups of animals and represent one of the most specialized systems of pollination mutualism. Studies have mainly focused on the association of fig trees and chalcid wasps. However, a number of non-wasp insects use figs as resource, showing a diversified range of ecological interactions. The community of non-wasp insects presented diversified feed regimes, such as insects that use figs to develop, seed predators, fig wasp predators and generalist insects. When pursuing my master's degree at University of São Paulo, advised by Dr. Rodrigo Augusto Santinelo Pereira , I found that the non-wasp community is as structured as the fig wasp community. This pattern, in addition to other biological data, suggest that this fauna may exert an important selective pressure on the fig reproduction.
As a post doc at the ARS-Research Participation Program with the Brunet Lab, I studied the population structure of wild carrots to understand the spread of cultivar genes into wild populations, and I tried to identify genetic markers to detect introgression using RADSeq (GBS) and a custom TASSEL pipeline.
My research focuses on a variety of questions related to the taxonomy and systematics of weevils, and their association with plants and endosymbiont bacteria. Below is a summary of projects I've been working on, and you can find more information about my research here.
Investigating the parallel evolution of morphology and endosymbiotic interactions in weevils
Diagramme showing the diversity of color patterns in Metamasius hemipterus
Associations of insects and microorganisms are common in the natural world and comprise countless examples of interactions, from parasitism to mutualism. In insects that feed upon nutrient-poor substrates, mutualistic associations involving bacteria have evolved repeatedly. As an honorary postdoctoral fellow advised by Dr. Prashant Sharma at the University of Wisconsin, my research focus on disentangling the parallel evolution of morphology and bacterial symbiosis in the Neotropical weevil genus Metamasius. An intriguing possibility exists that variation of elytra pigmentation across Metamasius species may be correlated with the relative abundance of their symbionts.
Systematics and biogeography of weevils associated with figs
The fig - fig wasp system is one of the most remarkable examples of broad radiations of insects on plants. Although this interaction has frequently been used as a model for studies of mutualism and coevolution, other groups of insects associated with fig trees have received less attention. The weevils (Coleoptera: Curculionidae) associated with figs are one notable example. Being the largest family of animals, weevils achieved great evolutionary success due to their early association with their host plants. Despite only a few reports in literature, there is strong evidence of the specialization of weevils on figs. During my PhD studies co-advised by Dr. Rodrigo Augusto Santinelo Pereira and Dr. Jean-Yves Rasplus, I tried to understand how the diversification of Curculionidae took place in fig trees. I found that at least 80 species of weevils belonging to five genera (Ceratopus, Omophorus, Carponinus, Curculio, and Indocurculio) are associated with figs.
Fig-weevils: Ceratopus (A,B), Omophorus (C), Curculio (D) and Carponinus (E,F).