Estudo do ataque da mariposa hyblaea sp. (lepidoptera: hyblaeiidae) em árvores de siriúba (avicenia germinans l.) em manguezais do estado do Pará, Brasil

Abstract

The moth Hyblaea sp. is an insect of great economic importance mainly due to its defoliating attack. The attack of this moth has been observed on siriuba trees (Avicenia germinans L., Verbenaceae), one of the dominant plants in Brazilian mangroves. This work intends to contribute to the knowledge of the coastal ecosystem by studying the seasonal fluctuation of Hyblaea sp. associated with the siriuba plants in parallel with the seasonal fluctuation of shrimp species in the mangroves of the coast of Pará. An attempt is being made to prove trophic relationships, as observed by traditional artisanal fishing communities that relate moth population peaks with shrimp peaks. The experiment is being carried out in the municipality of São Caetano de Odivelas. Suspended traps and nylon netting were installed to sample the moth and shrimp populations, respectively. The attack of herbivores on siriuba trees is studied periodically, calculating leaf loss by herbivore species. So far, in two bi-monthly samples, no Hyblaea sp. has been found on the trees. Two species of shrimp were collected, 90g of Nematopalaemon schmitti Holthins, 1950 and one young specimen of Macrobrachiun sp. Bate, 1888. The leaves of Avicenia germinans are being attacked by herbivores, in higher proportions on adult plants than on young ones. According to the data, it can be said that the populations, of Hyblea sp. and shrimps are at low rates in the months of February-April in relation to other quarters.