title: Microbial Communities of Lycaenid Butterflies Do Not Correlate with Larval Diet.
abstract: Herbivores possess many counteradaptations to plant defenses, and a growing body of research describes the role of symbiotic gut bacteria in mediating herbivorous diets among insects. However, persistent bacterial symbioses have not been found in Lepidoptera, despite the fact that perhaps 99% of the species in this order are herbivorous. We surveyed bacterial communities in the guts of larvae from 31 species of lycaenid butterflies whose caterpillars had diets ranging from obligate carnivory to strict herbivory. Contrary to our expectations, we found that the bacterial communities of carnivorous and herbivorous caterpillars do not differ in richness, diversity, or composition. Many of the observed bacterial genera are commonly found in soil and plant surfaces, and we detected known homopteran endosymbionts in the guts of homopterophagous species, suggesting that larvae acquire gut bacteria from their food and environment. These results indicate that lycaenid butterflies do not rely on specific bacterial symbioses to mediate their diverse diets, and provide further evidence of taxonomically depauperate bacterial communities among Lepidoptera.
authors.affiliation: Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, Harvard University, CambridgeMA, USA; Insect Symbiosis Research Group, Max Planck Institute for Chemical EcologyJena, Germany.
authors.forename: Melissa R L
authors.initials: MR
authors.lastname: Whitaker
authors.affiliation: Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, Harvard University, Cambridge MA, USA.
authors.forename: Shayla
authors.initials: S
authors.lastname: Salzman
authors.affiliation: Department of Pediatrics, University of California San Diego, La Jolla CA, USA.
authors.forename: Jon
authors.initials: J
authors.lastname: Sanders
authors.affiliation: Insect Symbiosis Research Group, Max Planck Institute for Chemical EcologyJena, Germany; Department for Evolutionary Ecology, Johannes Gutenberg UniversityMainz, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Kaltenpoth
authors.affiliation: Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, Harvard University, Cambridge MA, USA.
authors.forename: Naomi E
authors.initials: NE
authors.lastname: Pierce
keywords: Lepidoptera; Lycaenidae; aphytophagy; gut microbiome; herbivory; horizontal gene transfer