The pharyngeal taste organ of a blood-feeding insect functions in food recognition.

BACKGROUND: Obligate blood-feeding insects obtain the nutrients and water necessary to ensure survival from the vertebrate blood. The internal taste sensilla, situated in the pharynx, evaluate the suitability of the ingested food. Here, through multiple approaches, we characterized the pharyngeal organ (PO) of the hematophagous kissing bug Rhodnius prolixus to determine its role in food assessment. The PO, located antero-dorsally in the pharynx, comprises eight taste sensilla that become bathed with the incoming blood. RESULTS: We showed that these taste sensilla house gustatory receptor neurons projecting their axons through the labral nerves to reach the subesophageal zone in the brain. We found that these neurons are electrically activated by relevant appetitive and aversive gustatory stimuli such as NaCl, ATP, and caffeine. Using RNA-Seq, we examined the expression of sensory-related gene families in the PO. We identified gustatory receptors, ionotropic receptors, transient receptor potential channels, pickpocket channels, opsins, takeouts, neuropeptide precursors, neuropeptide receptors, and biogenic amine receptors. RNA interference assays demonstrated that the salt-related pickpocket channel Rproppk014276 is required during feeding of an appetitive solution of NaCl and ATP. CONCLUSIONS: We provide evidence of the role of the pharyngeal organ in food evaluation. This work shows a comprehensive characterization of a pharyngeal taste organ in a hematophagous insect.

Hunger- and thirst-sensing neurons modulate a neuroendocrine network to coordinate sugar and water ingestion.

Consumption of food and water is tightly regulated by the nervous system to maintain internal nutrient homeostasis. Although generally considered independently, interactions between hunger and thirst drives are important to coordinate competing needs. In Drosophila, four neurons called the interoceptive subesophageal zone neurons (ISNs) respond to intrinsic hunger and thirst signals to oppositely regulate sucrose and water ingestion. Here, we investigate the neural circuit downstream of the ISNs to examine how ingestion is regulated based on internal needs. Utilizing the recently available fly brain connectome, we find that the ISNs synapse with a novel cell-type bilateral T-shaped neuron (BiT) that projects to neuroendocrine centers. In vivo neural manipulations revealed that BiT oppositely regulates sugar and water ingestion. Neuroendocrine cells downstream of ISNs include several peptide-releasing and peptide-sensing neurons, including insulin producing cells (IPCs), crustacean cardioactive peptide (CCAP) neurons, and CCHamide-2 receptor isoform RA (CCHa2R-RA) neurons. These neurons contribute differentially to ingestion of sugar and water, with IPCs and CCAP neurons oppositely regulating sugar and water ingestion, and CCHa2R-RA neurons modulating only water ingestion. Thus, the decision to consume sugar or water occurs via regulation of a broad peptidergic network that integrates internal signals of nutritional state to generate nutrient-specific ingestion.

Hunger- and thirst-sensing neurons modulate a neuroendocrine network to coordinate sugar and water ingestion.

Consumption of food and water is tightly regulated by the nervous system to maintain internal nutrient homeostasis. Although generally considered independently, interactions between hunger and thirst drives are important to coordinate competing needs. In Drosophila , four neurons called the Interoceptive Subesophageal zone Neurons (ISNs) respond to intrinsic hunger and thirst signals to oppositely regulate sucrose and water ingestion. Here, we investigate the neural circuit downstream of the ISNs to examine how ingestion is regulated based on internal needs. Utilizing the recently available fly brain connectome, we find that the ISNs synapse with a novel cell type Bilateral T-shaped neuron (BiT) that projects to neuroendocrine centers. In vivo neural manipulations revealed that BiT oppositely regulates sugar and water ingestion. Neuroendocrine cells downstream of ISNs include several peptide-releasing and peptide-sensing neurons, including insulin producing cells (IPC), crustacean cardioactive peptide (CCAP) neurons, and CCHamide-2 receptor isoform RA (CCHa2R-RA) neurons. These neurons contribute differentially to ingestion of sugar and water, with IPCs and CCAP neurons oppositely regulating sugar and water ingestion, and CCHa2R-RA neurons modulating only water ingestion. Thus, the decision to consume sugar or water occurs via regulation of a broad peptidergic network that integrates internal signals of nutritional state to generate nutrient-specific ingestion.

The antennal transcriptome of Triatoma infestans reveals substantial expression changes triggered by a blood meal.

BACKGROUND: Triatoma infestans is the main vector of Chagas disease in the Americas, currently transmitting it in Argentina, Paraguay, and Bolivia. Many T. infestans populations present insecticide resistance, reducing the efficiency of control campaigns. Alternative vector control methods are needed, and molecular targets mediating fundamental physiological processes can be a promising option to manipulate kissing bug behavior. Therefore, it is necessary to characterize the main sensory targets, as well as to determine whether they are modulated by physiological factors. In order to identify gene candidates potentially mediating host cue detection, the antennal transcripts of T. infestans fifth instar larvae were sequenced and assembled. Besides, we evaluated whether a blood meal had an effect on transcriptional profiles, as responsiveness to host-emitted sensory cues depends on bug starvation. RESULTS: The sensory-related gene families of T. infestans were annotated (127 odorant receptors, 38 ionotropic receptors, 11 gustatory receptors, 41 odorant binding proteins, and 25 chemosensory proteins, among others) and compared to those of several other hemipterans, including four triatomine species. Several triatomine-specific lineages representing sensory adaptations developed through the evolution of these blood-feeding heteropterans were identified. As well, we report here various conserved sensory gene orthogroups shared by heteropterans. The absence of the thermosensor pyrexia, of pickpocket receptor subfamilies IV and VII, together with clearly expanded takeout repertoires, are revealed features of the molecular bases of heteropteran antennal physiology. Finally, out of 2,122 genes whose antennal expression was significantly altered by the ingestion of a blood meal, a set of 41 T. infestans sensory-related genes (9 up-regulated; 32 down-regulated) was detected. CONCLUSIONS: We propose that the set of genes presenting nutritionally-triggered modulation on their expression represent candidates to mediate triatomine host-seeking behavior. Besides, the triatomine-specific gene lineages found represent molecular adaptations to their risky natural history that involves stealing blood from an enormously diverse set of vertebrates. Heteropteran gene orthogroups identified may represent unknown features of the sensory specificities of this largest group of hemipteroids. Our work is the first molecular characterization of the peripheral modulation of sensory processes in a non-dipteran vector of human disease.

Molecular and functional basis of high-salt avoidance in a blood-sucking insect.

Salts are essential nutrients required for many physiological processes, and accordingly, their composition and concentration are tightly regulated. Taste is the ultimate sensory modality involved in resource quality assessment, resulting in acceptance or rejection. Here we found that high salt concentrations elicit feeding avoidance in the blood-sucking bug Rhodnius prolixus and elucidate the molecular and neurophysiological mechanisms involved. We found that high-salt avoidance is mediated by a salt-sensitive antennal gustatory receptor neuron (GRN). Using RNAi, we demonstrate that this process requires two amiloride-sensitive pickpocket channels (PPKs; Rpro PPK014276 and Rpro PPK28) expressed within these cells. We found that antennal GRNs project to the insect primary olfactory center, the antennal lobes, revealing these centers as potential sites for the integration of taste and olfactory host-derived cues. Moreover, the identification of the gustatory basis of high-salt detection in a hematophagous insect suggests novel targets for the prevention of biting and feeding.

Evolution of the Insect PPK Gene Family.

Insect pickpocket (PPK) receptors mediate diverse functions, among them the detection of mechano- and chemo-sensory stimuli. Notwithstanding their relevance, studies on their evolution only focused on Drosophila. We have analyzed the genomes of 26 species of eight orders including holometabolous and hemimetabolous insects (Blattodea, Orthoptera, Hemiptera, Phthiraptera, Hymenoptera, Lepidoptera, Coleoptera, and Diptera), to characterize the evolution of this gene family. PPKs were detected in all genomes analyzed, with 578 genes distributed in seven subfamilies. According to our phylogeny, ppk17 is the most divergent member, composing the new subfamily VII. PPKs evolved under a gene birth-and-death model that generated lineage-specific expansions usually located in clusters, while purifying selection affected several orthogroups. Subfamily V was the largest, including a mosquito-specific expansion that can be considered a new target for pest control. PPKs present a high gene turnover generating considerable variation. On one hand, Musca domestica (59), Aedes albopictus (51), Culex quinquefasciatus (48), and Blattella germanica (41) presented the largest PPK repertoires. On the other hand, Pediculus humanus (only ppk17), bees, and ants (6-9) had the smallest PPK sets. A subset of prevalent PPKs was identified, indicating very conserved functions for these receptors. Finally, at least 20% of the sequences presented calmodulin-binding motifs, suggesting that these PPKs may amplify sensory responses similarly as proposed for Drosophila melanogaster ppk25. Overall, this work characterized the evolutionary history of these receptors revealing relevant unknown gene sequence features and clade-specific expansions.

Learning Spatial Aversion Is Sensory-Specific in the Hematophagous Insect Rhodnius prolixus.

Even though innate behaviors are essential for assuring quick responses to expected stimuli, experience-dependent behavioral plasticity confers an advantage when unexpected conditions arise. As being rigidly responsive to too many stimuli can be biologically expensive, adapting preferences to time-dependent relevant environmental conditions provide a cheaper and wider behavioral reactivity. According to their specific life habits, animals prioritize different sensory modalities to maximize environment exploitation. Besides, when mediating learning processes, the salience of a stimulus usually plays a relevant role in determining the intensity of an association. Then, sensory prioritization might reflect an heterogeneity in the cognitive abilities of an individual. Here, we analyze in the kissing bug Rhodnius prolixus if stimuli from different sensory modalities generate different cognitive capacities under an operant aversive paradigm. In a 2-choice walking arena, by registering the spatial distribution of insects over an experimental arena, we evaluated firstly the innate responses of bugs confronted to mechanical (rough substrate), visual (green light), thermal (32°C heated plate), hygric (humidified substrate), gustatory (sodium chloride), and olfactory (isobutyric acid) stimuli. In further experimental series bugs were submitted to an aversive operant conditioning by pairing each stimulus with a negative reinforcement. Subsequent tests allowed us to analyze if the innate behaviors were modulated by such previous aversive experience. In our experimental setup mechanical and visual stimuli were neutral, the thermal cue was attractive, and the hygric, gustatory and olfactory ones were innately aversive. After the aversive conditioning, responses to the mechanical, the visual, the hygric and the gustatory stimuli were modulated while responses to the thermal and the olfactory stimuli remained rigid. We present evidences that the spatial learning capacities of R. prolixus are dependent on the sensory modality of the conditioned stimulus, regardless their innate valence (i.e., neutral, attractive, or aversive). These differences might be given by the biological relevance of the stimuli and/or by evolutionary aspects of the life traits of this hematophagous insect.

Nitric oxide contributes to high-salt perception in a blood-sucking insect model.

In all organisms, salts produce either appetitive or aversive responses depending on the concentration. While low-salt concentration in food elicits positive responses to ingest, high-salt triggers aversion. Still the mechanisms involved in this dual behavior have just started to be uncovered in some organisms. In Rhodnius prolixus, using pharmacological and behavioral assays, we demonstrated that upon high-salt detection in food a nitric oxide (NO) dependent cascade is activated. This activation involves a soluble guanylate cyclase (sGC) and the production of cyclic guanosine monophosphate (cGMP). Thus, appetitive responses to low-salt diets turn to aversion whenever this cascade is activated. Conversely, insects feed over aversive high-salt solutions when it is blocked by reducing NO levels or by affecting the sGC activity. The activation of NO/sGC/cGMP cascade commands the avoidance feeding behavior in R. prolixus. Investigations in other insect species should examine the possibility that high-salt aversion is mediated by NO/sSG/cGMP signaling.

Salt controls feeding decisions in a blood-sucking insect.

Salts are necessary for maintaining homeostatic conditions within the body of all living organisms. Like with all essential nutrients, deficient or excessive ingestion of salts can result in adverse health effects. The taste system is a primary sensory modality that helps animals to make adequate feeding decisions in terms of salt consumption. In this work we show that sodium and potassium chloride salts modulate the feeding behavior of Rhodnius prolixus in a concentration-dependent manner. Feeding is only triggered by an optimal concentration of any of these salts (0.1-0.15M) and in presence of the phagostimulant ATP. Conversely, feeding solutions that do not contain salts or have a high-salt concentration (>0.3M) are not ingested by insects. Notably, we show that feeding decisions of insects cannot be explained as an osmotic effect, because they still feed over hyperosmotic solutions bearing the optimal salt concentration. Insects perceive optimal-salt, no-salt and high-salt solutions as different gustatory information, as revealed the electromyogram recordings of the cibarial pump. Moreover, because insects do a continuous gustatory monitoring of the incoming food during feeding, sudden changes beyond the optimal sodium concentration decrease and even inhibit feeding. The administration of amiloride, a sodium channel blocker, noticeably reduces the ingestion of the optimal sodium solution but not of the optimal potassium solution. Salt detection seems to occur at least through two salt receptors, one amiloride-sensitive and another amiloride-insensitive. Our results confirm the importance of the gustatory system in R. prolixus, showing the relevant role that salts play on their feeding decisions.

Kissing bugs can generalize and discriminate between different bitter compounds.

Animals make use of contact chemoreception structures to examine the quality of potential food sources. During this evaluation they can detect nutritious compounds that promote feeding and recognize toxins that trigger evasive behaviors. Although animals can easily distinguish between stimuli of different gustatory qualities (bitter, salty, sweet, etc.), their ability to discriminate between compounds of the same quality may be limited. Numerous plants produce alkaloids, compounds that elicit aversive behaviors in phytophagous insects and almost uniformly evoke a bitter taste for man. In hematophagous insects, however, the effect of feeding deterrent molecules has been barely studied. Recent studies showed that feeding in Rhodnius prolixus can be negatively modulated by the presence of alkaloids such as quinine (QUI) and caffeine (CAF), compounds that elicit similar aversive responses. Here, we applied associative and non-associative learning paradigms to examine under two behavioral contexts the ability of R. prolixus to distinguish, discriminate and/or generalize between these two bitter compounds, QUI and CAF. Our results show that bugs innately repelled by bitter compounds can change their behavior from avoidance to indifference or even to preference according to their previous experiences. After an aversive operant conditioning with QUI or CAF, R. prolixus modified its behavior in a direct but also in a cross-compound manner, suggesting the occurrence of a generalization process between these two alkaloids. Conversely, after a long pre-exposure to each alkaloid, bugs decreased their avoidance to the compound used during pre-exposure but still expressed an avoidance of the novel compound, proving that QUI and CAF are detected separately. Our results suggest that R. prolixus is able to discriminate between QUI and CAF, although after an associative conditioning they express a symmetrical cross-generalization. This kind of studies adds insight into the gustatory sense of a blood-sucking model but also into the learning abilities of hematophagous insects.

Bitter stimuli modulate the feeding decision of a blood-sucking insect via two sensory inputs.

The gustatory system of animals is involved in food quality assessment and controls the feeding decision of an individual confronted with a potential alimentary source. Triatomines are haematophagous insects that feed on vertebrate blood. Once they reach a potential host, they walk over the host skin searching for an adequate site to pierce. Then, they insert their stylets and take a first sampling gorge to decide whether food is acceptable. Our work reveals that the presence of bitter compounds inhibits the feeding behavior of these bugs. Firstly, triatomines decreased their feeding behavior if substrates spread with quinine or caffeine were detected by external receptors localized exclusively in the antennae. Morphological inspections along with electrophysiological recordings revealed the existence of four gustatory sensilla located in the tip of the antenna that respond to both bitter tastants. The absence of these bitter detectors by antennal ablation reversed the observed feeding inhibition evoked by bitter compounds. Secondly, once triatomines pumped the first volume of food with bitter compounds (quinine, caffeine, berberine, salicin), a decrease in their feeding behavior was observed. Morphological inspections revealed the existence of eight gustatory sensilla located in the pharynx that might be responsible for the internal bitter detection. Finally, we found that a brief pre-exposure to bitter compounds negatively modulates the motivation of bugs to feed on an appetitive solution. Results presented here highlight the relevance of bitter taste perception in the modulation of the feeding behavior of a blood-sucking insect.

Flight initiation by male Rhodnius prolixus is promoted by female odors.

Several triatomine bug species utilize chemical cues for sexual communication. We tested whether female or male Rhodnius prolixus, a vector of Chagas disease, produce volatile chemicals that elicit flight responses from conspecifics, and then isolated the source of the chemical. Males confronted with an airstream containing female odors showed a significantly greater take-off frequency compared to a blank airstream or an airstream with male odors. In contrast, females exhibited similar take-off frequencies to male or female odor as to a clean airstream. Occlusion of female metasternal glands with paraffin wax resulted in a significant decrease in male take-off frequency compared to that of intact females. Additionally, excised female metasternal glands elicited a similar take-off frequency from males as did intact females, both significantly greater than the take-off frequency to clean air. These results show that R. prolixus females release a pheromone from their metasternal glands that causes upwind flight in conspecific males.

Comportamento sexual de Rhodnius prolixus (Heteroptera: Reduviidae)

Este estudo descreveu a dinâmica de uso de abrigos em adultos de Rhodnius prolixus evidenciando que a saída dos abrigos e a atividade locomotora dos machos são moduladas por sinais olfativos sexuais emitidos por fêmeas. Adicionalmente, foram analisadas a frequência de início do vôo, e a atividade locomotora durante a marcha, a fim de avaliar as hipóteses de que haveria ativação e orientação mediante sinais químicos emitidos por indivíduos do sexo oposto. Além disso, verificamos o comportamento de agregação de machos ao redor de casais em cópula. Os odores das fêmeas foram capazes de induzir a saída dos machos dos abrigos, além de aumentar a atividade locomotora destes. Odores de fêmeas originados das glândulas metasternais promoveram um aumento na frequência de inicio do voo de. machos de R. prolixus. Além disso, estes sinais olfativos modularam a orientação anemotática observada durante a marcha dos machos. Nossos achados demonstraram que na ausência dos odores das glândulas metasternais de fêmeas, o comportamento de agregação dos machos durante a cópula é drasticamente afetado. Desta forma, concluímos que os odores produzidos pelas glândulas metasternais das fêmeas são de grande relevância no comportamento sexual de R. prolixus, já que na ausência destes, alguns mecanismos que medeiam o comportamento sexual desta espécie foram prejudicados.

Comportamento sexual de Rhodnius prolixus (Heteroptera: Reduviidae) / Sexual behavior of Rhodnius prolixus (Heteroptera: Reduviidae)

Este estudo descreveu a dinâmica de uso de abrigos em adultos de Rhodnius prolixus evidenciando que a saída dos abrigos e a atividade locomotora dos machos são moduladas por sinais olfativos sexuais emitidos por fêmeas. Adicionalmente, foram analisadas a frequência de início do vôo, e a atividade locomotora durante a marcha, a fim de avaliar as hipóteses de que haveria ativação e orientação mediante sinais químicos emitidos por indivíduos do sexo oposto. Além disso, verificamos o comportamento de agregação de machos ao redor de casais em cópula. Os odores das fêmeas foram capazes de induzir a saída dos machos dos abrigos, além de aumentar a atividade locomotora destes. Odores de fêmeas originados das glândulas metasternais promoveram um aumento na frequência de inicio do voo de. machos de R. prolixus. Além disso, estes sinais olfativos modularam a orientação anemotática observada durante a marcha dos machos. Nossos achados demonstraram que na ausência dos odores das glândulas metasternais de fêmeas, o comportamento de agregação dos machos durante a cópula é drasticamente afetado. Desta forma, concluímos que os odores produzidos pelas glândulas metasternais das fêmeas são de grande relevância no comportamento sexual de R. prolixus, já que na ausência destes, alguns mecanismos que medeiam o comportamento sexual desta espécie foram prejudicados.

Metasternal gland volatiles and sexual communication in the triatomine bug, Rhodnius prolixus.

Twelve compounds produced by the metasternal glands (MGs) of the triatomine bug Rhodnius prolixus were identified by solid phase microextraction (SPME) combined with coupled gas chromatography-mass spectrometry (GC-MS) using achiral and chiral columns. All substances were ketones or alcohols, and the same compound profile was found in the secretions produced by either sex. The most abundant compounds were 2-methyl-3-buten-2-ol, (2S)-pentanol, (3E)-2-methyl-3-penten-2-ol, and (2R/2S)-4-methyl-3-penten-2-ol. Emission of these compounds was detected more frequently from females than males, and females released them more frequently during the early hours of the scotophase, the period when sexual activity in this species is at its peak. These compounds were also detected in the headspace above mating pairs. Finally, the occlusion of the MG orifices of male or female bugs with paraffin resulted in a significant decrease in copulation frequency compared to sham-operated insects. Together, these data suggest that the MG secretions of R. prolixus may be involved in sexual communication.

Sinais químicos envolvidos no comportamento sexual de Rhodnius prolixus Stål, 1859(Hemiptera, Reduviidae)

Rhodnius prolixus é o principal vetor da doença de Chagas no norte da América do Sul e na América Central. Triatomíneos adultos possuem um par de glândulas metasternais (GM) localizadas no metatórax ventral. Alguns estudos discutem a participação das GMs na comunicação sexual em triatomíneos. Até o momento, a função das GMs de R. prolixus, assim como a identidade da suas secreções são desconhecidas. Assim, o objetivo deste estudo foi identificar os compostos presentes nas GMs de R. prolixus, bem como estudar o envolvimento destes compostos no contexto sexual desta espécie. Para isso, foram feitas análises. químicas do conteúdo das GMs, utilizando SPME e CG-EM. Posteriormente,. foram feitas análises químicas dos voláteis emitidos por casais em cópula. A emissão espontânea de voláteis em adultos virgens também foi caracterizada. Foram identificados 12 compostos nas GMs, sendo estes cetonas e álcoois.

Os mesmos compostos foram encontrados nas glândulas de ambos os sexos. Em 70% das cópulas realizadas foi encontrado pelo menos um composto das GMs, sendo que o principal composto (2-metil-3-buten-2-ol) foi detectado em 40% das cópulas. As fêmeas emitiram espontaneamente mais compostos presentes nas GM durante a noite, sendo esta emissão mais intensa que nos machos. Propomos que os compostos encontrados nas GMs de R. prolixus estão envolvidos na comunicação sexual desta espécie. Foi observado um decréscimo no sucesso da cópula na ausência dos odores das GMs devido a oclusão dos orifícios de abertura desta glândula. Sugerimos que o reconhecimento entre os sexos pode ser mediado por sinais químicos e que estes podem ser originados das GMs. A identificação dos compostos presentes nas GMs, assim como o envolvimento destes na comunicação química, é o primeiro passo no estudo dos prováveis feromônios sexuais de R. prolixus. A sua potencial utilização na manipulação do comportamento desta espécie justifica o aprofundamento deste estudo para permitir o desenho potencial de ferramentas para o seu controle

Sinais químicos envolvidos no comportamento sexual de Rhodnius prolixus Stål, 1859(Hemiptera, Reduviidae) / Monitoring susceptibility to pyrethroid deltamethrin in populations of Triatoma sordida Stål, 1859 (Hemiptera: Reduviidae)

Rhodnius prolixus é o principal vetor da doença de Chagas no norte da América do Sul e na América Central. Triatomíneos adultos possuem um par de glândulas metasternais (GM) localizadas no metatórax ventral. Alguns estudos discutem a participação das GMs na comunicação sexual em triatomíneos. Até o momento, a função das GMs de R. prolixus, assim como a identidade da suas secreções são desconhecidas. Assim, o objetivo deste estudo foi identificar os compostos presentes nas GMs de R. prolixus, bem como estudar o envolvimento destes compostos no contexto sexual desta espécie. Para isso, foram feitas análises. químicas do conteúdo das GMs, utilizando SPME e CG-EM. Posteriormente,. foram feitas análises químicas dos voláteis emitidos por casais em cópula. A emissão espontânea de voláteis em adultos virgens também foi caracterizada. Foram identificados 12 compostos nas GMs, sendo estes cetonas e álcoois.

Os mesmos compostos foram encontrados nas glândulas de ambos os sexos. Em 70% das cópulas realizadas foi encontrado pelo menos um composto das GMs, sendo que o principal composto (2-metil-3-buten-2-ol) foi detectado em 40% das cópulas. As fêmeas emitiram espontaneamente mais compostos presentes nas GM durante a noite, sendo esta emissão mais intensa que nos machos. Propomos que os compostos encontrados nas GMs de R. prolixus estão envolvidos na comunicação sexual desta espécie. Foi observado um decréscimo no sucesso da cópula na ausência dos odores das GMs devido a oclusão dos orifícios de abertura desta glândula. Sugerimos que o reconhecimento entre os sexos pode ser mediado por sinais químicos e que estes podem ser originados das GMs. A identificação dos compostos presentes nas GMs, assim como o envolvimento destes na comunicação química, é o primeiro passo no estudo dos prováveis feromônios sexuais de R. prolixus. A sua potencial utilização na manipulação do comportamento desta espécie justifica o aprofundamento deste estudo para permitir o desenho potencial de ferramentas para o seu controle