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Parasitoids have evolved mechanisms to evade their hosts' defenses. Bracon vulgaris (Ashmead) is a larval ectoparasitoid responsible for natural reduction of Anthonomus grandis (Boheman) and Pectinophora gossypiella (Saunders), which are considered the main cotton pests in the cotton agro ecosystem in northeastern Brazil. This study aimed to analyze the sensory structures (antennae and ovipositor) involved in the parasitism behavior of B. vulgaris, and to describe and evaluate associations between composition, morphology, and functions of these structures in the parasitoid-host interaction. Results showed that the B. vulgaris ovipositor is a multifunctional structure of 2.7 ± 0.3 mm in length composed of 3 valves. Valves 1 and 2 are elongated, rigid, and act jointly to pierce the host's cuti cle, to inject the poison glands secretion, and to deposit eggs. Valve 3 covers the other valves, giving them protection. Valve 3 also presents annulations in all its extension, which gives flexibility to the ovipositor, and trichoid sensilla that possibly capture vibrations from the host's feeding and loco motion, thereby aiding the parasite in the host selection. The presence of cuticular microtrichia was possibly responsible for the cleaning of the ovipositor, keeping it functional between the various inser tions that occur during the parasitism behavior. The parasitoid's antennae are filliform-like, measure about 2 mm, and are composed of four types of sensilla (trichoids, basiconical, coeloconical, and pla codes) that act as olfactory and gustatory receptors and/or express tactile, thermo,-and hygroreception functions. The integrated action of these sensory components corroborates the successful parasitism behavior of the parasitoid B. vulgaris.

Indiscriminate disposal of residues of domestic and/or industrial origin in aquatic ecosystems resulting from urban activities causes concern about their effects on the fauna. Substances absorbed by animals, such as those cited above, are metabolized by the liver, as it is the main target organ of several pollutants and also exercises basic vital functions in the organism. For this reason the liver is used as the main and most reliable biomarker in environmental studies. Thus the objective of the present study was to identify hepatic alterations resulting from exposure to water contaminated by a few commercial brands of biodegradable detergents and their effects when present together with several other contaminants found in nature. For such, a solution of 1 ppm of biodegradable detergents and water from an urban lake were tested on two widely distributed native Brazilian fish (Astyanax altiparanae and Prochilodus lineatus). Several alterations were found on the liver, including cytoplasm vacuolization, nuclear displacement, macrophage recruitment and reduced liver glycogen, showing a degenerative process in the liver of the fish, due to the action of contaminants.

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