Chemical convergence between a guild of facultative myrmecophilous caterpillars and host plants

Autor(es)

Lima, Luan Dias ^[1] ; Trigo, Jose Roberto ^[2] ; Kaminski, Lucas Augusto ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Rio Grande do Sul, Dept Zool, Programa Posgrad Biol Anim, BR-91501970 Porto Alegre, RS - Brazil

^[2] Univ Estadual Campinas, Dept Biol Anim, Inst Biol, Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ECOLOGICAL ENTOMOLOGY; v. 46, n. 1 SEP 2020.
• Citações Web of Science: 0

Resumo

1. Ants exert strong selective pressure on herbivorous insects, although some caterpillars can live in symbiosis with them using chemical defensive strategies. 2. We investigated the adaptive resemblance of cuticular hydrocarbons (CHCs) in multitrophic systems involving a guild of facultative myrmecophilous caterpillar species (Lepidoptera: Lycaenidae), tending ants (Hymenoptera: Formicidae), and host plants from three families. We hypothesised that the CHCs of the caterpillars would resemble those of their host plants (chemical camouflage). 3. We analysed CHCs using gas chromatography/mass spectrometry. Morisita's similarity index (SI) was used to compare CHC profiles of caterpillar species with different types of ant associations (commensal or mutualistic), ants, and host plants. 4. We found strong convergence between caterpillars' CHCs and plants, especially for commensal species that do not provide secretion rewards for ants. Moreover, we found unexpected chemical convergence among mutualistic (trophobiotic) caterpillar species that offer caloric reward secretions to ants. 5. These results show that the studied caterpillars acquire CHCs through their diet and that they vary according to host plant species and type of ant association (commensalism or mutualism). This `chemical camouflage' of myrmecophilous caterpillars may have arisen as a defensive strategy allowing coexistence with ants on plants, whereas `chemical conspicuousness' may have evolved in the context of honest signalling between mutualistic partners. 6. We suggest the existence of chemical mimicry among myrmecophilous species, especially between mutualistic caterpillars. Cuticular chemical mixtures can play a key adaptive role in decreasing ant attacks and increasing caterpillar survival in multimodal sensory systems. (AU)

• Processo FAPESP: 11/17708-0 - Defesas químicas em plantas e insetos neotropicais
• Beneficiário: Jose Roberto Trigo
• Linha de fomento: Auxílio à Pesquisa - Regular
• Processo FAPESP: 10/51340-8 - Interações simbióticas entre larvas de borboletas e formigas: história natural, morfologia e padrões no uso de plantas hospedeiras
• Beneficiário: Lucas Augusto Kaminski
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado