Building of Leaf Shelters by Stenoma scitiorella Walker (Lepidoptera: Elachistidae): Manipulation of Host Plant Quality?

Abstract

Construção de Abrigos Foliares por Stenoma scitiorella Walker (Lepidoptera: Elachistidae):Manipulação da Qualidade da Planta Hospedeira?RESUMO -A construção de abrigos foliares é um comportamento comum entre lagartas de microlepidópteros e, ao que parece, tais abrigos proporcionam um refúgio contra as intempéries e o ataque de predadores e parasitóides. Estudos recentes sobre a ecologia nutricional de insetos têm sugerido que tal comportamento seria, na realidade, uma estratégia evolutivamente selecionada para maximizar a qualidade da planta hospedeira que consomem. As lagartas de Stenoma scitiorella Walker unem as folhas jovens de Xylopia aromatica (Lam.) Mart. (Annonaceae) para a construção de um abrigo no qual se refugiam alimentando-se exclusivamente das folhas internas. Por proporcionar as melhores condições para o desenvolvimento larval, a maioria dos abrigos foliares (53,4%) é ocupada por apenas uma lagarta. Os resultados revelaram que, apesar de alterar os teores de água e carboidratos solúveis, a construção dos abrigos foliares não afeta a concentração de taninos nem a preferência das lagartas por folhas externas ou internas. Assim, tal comportamento não representa uma estratégia adaptativa do inseto para superar as defesas químicas da planta hospedeira. Dessa forma, é provável que os abrigos foliares de S. scitiorella sejam construídos para outros fins como, por exemplo, proteção das lagartas contra dessecação ou predação.PALAVRAS-CHAVE: Cerrado, herbivoria, lagarta, tanino, Xylopia aromatica ABSTRACT -Building of leaf shelters is a widespread behavior among microlepidopteran larvae. Apparently, these shelters provide refuge to caterpillars against bad weather and reduce the risks of predation and parasitism. Recent studies about nutritional ecology of insects have suggested that such behavior would actually be an strategy evolutionarily selected to maximize the quality of the host plant consumed by them. Stenoma scitiorella Walker caterpillars tie together young Xylopia aromatica (Lam.) Mart. (Annonaceae) leaves to build a shelter in which they retreat, feeding exclusively on inner leaves. The accumulation of damage and excrement in leaf shelters with several caterpillars may lead to a decline in larval development and survivorship. For providing the best conditions for larval development most leaf shelters (53,4%) are occupied by only one caterpillar. Although altering the water and soluble carbohydrates contents, the building of shelters did not affect either the tannins concentrations or the preference of caterpillars for external or internal leaves. Hence, probably this behavior does not denote an adaptative strategy of the insect to overcome the host plant chemical defenses. Thus, it is possible that the leaf shelters of S. scitiorella caterpillars are built for other purposes as, for example, to protect caterpillars from desiccation and predation.KEY WORDS: Cerrado, herbivory, caterpillar, tannin, Xylopia aromatica known as allelochemicals. Allelochemicals differently from amino acids, carbohydr...

Insect-plant interactions: new pathways to a better comprehension of ecological communities in Neotropical savannas

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Biology and occurrence of Inga Busk species (Lepidoptera: Oecophoridae) on Cerrado host plants

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Ecological consequences of shelter sharing by leaf‐tying caterpillars

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