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Olfactory behaviors serve a wide variety of social functions in mammals. Odor may signal information about attributes of individuals important for mating and reproduction. Olfactory behaviors, such as scent-marking, may also function as part of home range or resource defense strategies. We assessed the potential social and home range defense functions of olfactory behavior in a pair-living and sexually monogamous primate, Azara's owl monkey (Aotus azarae), in the Argentinian Chaco. This is the most extensive investigation of owl monkey olfactory behaviors in the wild. Individuals regularly performed olfactory behaviors (group mean + SD = 1.3 + 0.5 per hour). The patterns were generally comparable to those observed in studies of captive owl monkeys, except that urine washing was the most common behavior in the wild, as opposed to scent-marking and genital inspections. Most olfactory behaviors were performed by adults, and there were striking sex differences in genital inspections: almost all consisted of an adult male inspecting the paired adult female. These findings suggest that olfactory behaviors play an important role in signaling and coordinating reproduction among owl monkeys, particularly during periods of female conception and pregnancy. Additionally, our research indicates that these behaviors may also serve as a defense strategy for maintaining the core area of their home ranges. This study offers the first assessment of the role of olfactory behaviors in reproductive contexts and home range defense in pair-living, monogamous platyrrhine primates.

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Drosophila suzukii (Matsumura) is an exotic pest of economic importance that affects several soft-skinned fruits in Mexico. Previously, we found that yellow or yellow-green rectangular cards inside a transparent trap baited with attractants improved D. suzukii capture. In this study, we evaluated the influence of rectangular cards with different yellow shades inside a transparent multi-hole trap baited with apple cider vinegar (ACV) on D. suzukii capture in the field. Second, we tested whether ACV-baited traps with cards of other geometric shapes affected D. suzukii catches compared to traps with rectangular cards. Third, we evaluated the effects of commercial lures combined with a more efficient visual stimulus from previous experiments on trapping D. suzukii flies. We found that ACV-baited traps plus a yellow-shaded rectangle card with 67% reflectance at a 549.74 nm dominant wavelength captured more flies than ACV-baited traps with yellow rectangle cards with a higher reflectance. Overall, ACV-baited traps with rectangles and squares caught more flies than did ACV-baited traps without visual stimuli. The traps baited with SuzukiiLURE-Max, ACV and Z-Kinol plus yellow rectangles caught 57, 70 and 101% more flies, respectively, than the traps baited with the lure but without a visual stimulus.

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ABSTRACT The present study describes the morphology of the antennal sensilla of adults of Gymnetis holosericea (Voet, 1779) and Gymnetis rufilateris (Illiger, 1800). The adults of Gymnetis spp. were sexed and antenna of males and females were dissected. Both species have sensilla chaetica, trichodea, placodea (type I and II), coeloconica (type I and II), and ampullacea (or pore). Females of G. holosericea have a total of about 19,995 sensilla and males have about 23,273 sensilla, and females of G. rufilateris have about 16,633 sensilla and males have about 21,184 sensilla. Sensilla placodea are the predominant type of sensilla in males and females of G. holosericea and G. rufilateris.

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In this study, we described immediate/acute reactions to stress-related chemical cues (SC - Stress Cue) in fish. Specifically, we evaluated the effects of SC on ventilation rate (VR) and feeding behavior in Nile tilapia (Oreochromis niloticus), a highly relevant species for world aquaculture, therefore, to understand the diversity of stressful contexts and stress responses in this species have important practical applications (stress reduction). Stress cue was obtained from conspecifics exposed to a handling stressor. Stress was confirmed by measuring plasma cortisol levels. The responses to SC were contrasted to chemical control cues: a cue originated from non-stressed conspecifics and pure water (vehicle control). We observed that Nile tilapia exposed to SC had an increase in VR, but without effects on feeding behavior (feeding latency and ingestion). Thus, the SC is a stressor that induces readily stress response (VR increase), suggesting sympathetic activation, but did not change feeding performance. In practical terms, it is positive because although social propagation of stress via SC elicits a stress response, it did not harm appetite.

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Alphitobius diaperinus is one of the most significant pests in the poultry industry. Identifying the role of self-produced chemical signals can help control it. Here, we exposed adults to the olfactory signals of other adults of similar and different genders (either males or females) and sexual experiences (i.e., virgin and experienced) to assess their long-range attractiveness and, at short-range, their mating behavior responses (i.e., touching, mounting, and copulation). In olfactometric experiments, our results indicate that adults are attracted to the olfactory signals of other male adults, independently of gender, or sexual condition, indicating the presence of generalized long-range attractive signals, in contrast to female signals, can be both factor-dependent. However, in mating experiments, virgin males developed more robust mating responses (i.e., they mount and copulate longer with females) compared to sexually experienced males, even though they both have similar precopulatory behavioral responses (i.e., time of antennal and leg touching). These results address the importance of short-range chemical signals in eliciting copulation. Furthermore, when virgins of both genders were tested, their mating responses were significantly longer than any other pair combination, indicating that sexual experience also affects mating behavior. Chemical analyses of adult extracts showed that sexual experience, but not gender, is linked to differences in chemical profiles of adults, primarily involved in short-range signaling. These findings provide new insights into the attractiveness and mating responses of A. diaperinus and the role of sexual experience in shaping the behavior and chemical profile of insects that mate multiple times during their lifetime.

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Cuticular hydrocarbons (CHCs) of most terrestrial arthropods primarily serve as a protective barrier against desiccation and infection. Throughout evolution, these compounds have acquired another fundamental function: the exchange of signals during interactions between nestmates. However, even though cuticular hydrocarbons perform a dual function in social insects, little is known about the effect(s) of one function on the other in social insects, and no study has evaluated this relationship in social wasps. Therefore, the present study tests the hypothesis that the level of aggressiveness presented during induced encounters between nestmates of Polybia paulista who were subjected to different conditions temperature is different than between nestmates who remained under the same temperature conditions. If the hypothesis is confirmed, it is likely because the cuticle of the wasps that had been exposed to temperature variation adjusted to these conditions leading them not to recognize the cuticular chemical signature of their colony. To test this hypothesis, workers were exposed to temperature variation in a BOD chamber and then subjected to encounters with workers who were maintained at a constant temperature of 24℃. We also used control groups to evaluate the effect of isolation alone among the groups. According to our results, our hypothesis was confirmed, the level of aggressiveness presented between nestmates who were exposed to temperature variation and those who remained at 24℃ was significantly higher than the levels of aggressiveness presented between nestmates who remained isolated but under constant temperature during the same period, in some cases, it was similar to the aggressiveness presented in encounters between wasps from different colonies. During these encounters, wasps performed alarm behavior, bites, and stings not seen during encounters between wasps that remained under the same temperature, but in isolated groups. The lack of aggressive behavior under isolated conditions indicates that isolation had no effect on chemical recognition signature. These results suggest that temperature variation may have caused some change in the cues that allow recognition between nestmates. On the other hand, these results were not caused by isolation or stress generated by the study design and difference in the CHC profile of workers, as described in the literature, is consistent with our results.(AU)

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Chemical communication can induce a multitude of behaviours when detected by fish olfactory systems, from parental care, predation and alarm signalling, to foraging, schooling, reproduction, and migration. Chemical cues provide information that visual traits cannot and fish can respond to chemical cues without any additional sensory cue. In this way, pheromones play an essential role in the fitness of fishes. Given that Aphyocharax anisitsi inhabits environments characterized by cloudy and highly vegetated waters, it is interesting to evaluate the olfactory contribution in their communication. Here, we investigated the relevance of chemical cues in the types of behaviours triggered in A anisitsi by two experimental contexts: 1) non-social and olfactory context (conspecific-chemical cues), and 2) social context (conspecific female or male presence). Non-social context experiments suggest that males of A. anisitsi respond to both male and female-chemical cues even in the absence of other sensory inputs. The high olfactory sensitivity of characids in general and of A. anisitsi, in particular, could facilitate vital functions, such as foraging and conspecific recognition in habitats that impose severe restrictions on the visual system.

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BACKGROUND: Poison frogs are known for the outstanding diversity of alkaloid-based chemical defences with promising therapeutic applications. However, current knowledge about chemical defences in Dendrobatoidea superfamily has two sources of bias. First, cryptic, brown-colored species have been neglected in comparison to those conspicuously colored, and second, there has been little interest in characterizing metabolites other than alkaloids mediating defensive functions. In an effort to contribute to fill the gap of knowledge about cryptic species and broadening the spectrum of compounds analyzed we have applied head-space solid phase microextraction coupled to gas chromatography and mass spectrometry (HS-SPME/GC-MS) for extracting amphibian alkaloids and volatile organic compounds (VOCs) from Silverstoneia punctiventris. RESULTS: Using the skin from 8 specimens in 4 biological replicates we have found 33 different compounds. Twenty of them were classified as VOCs into 15 chemical classes including alkanes, alcohols, carbonyl compounds, methylpyridines, benzothiazoles, N-alkylpyrrolidines, pyrazines, and sesquiterpenoids, some of which were previously reported as repellents, defence compounds or defence pheromones in other organisms, and as sex pheromones in a treefrog. Interestingly, six of the remaining compounds were identified as alkaloids previously reported in other toxic/unpalatable dendrobatid frogs. CONCLUSIONS: This is the first report of alkaloids and VOCs found in the Silverstoneia genus, which has been assumed for decades as non-chemically defended. This study establishes HS-SPME/GC-MS as a new application for a simultaneous approach to amphibian alkaloids and VOCs in poison frogs while opens up new research questions to assess the co-occurrence of both type of compounds and to investigate the evolutionary significance of a defence gradient that includes olfactory avoidance, unpalatability, and toxicity in dendrobatids. In addition, our results show that amphibian alkaloids could have a dual function (olfactory at distance, taste by contact) never explored before neither in Silverstonaeia nor in any other dendrobatid species.

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Sexual pheromones are chemical molecules responsible for mediating sex recognition and mating events. Long- and close-range sexual pheromones act differently. The first type is released to attract potential partners, whereas the second coordinates the interactions after potential mating partners encounter each other. Cuticular hydrocarbons (CHCs) have been suggested to be important cues in the mating systems of several Hymenoptera species, although empirical data are still lacking for many species. Here, we evaluated whether males of the model species Polistes dominula can differentiate the sex of individuals based on their CHC composition. In August 2019, several post-worker emergent nests (n = 19) were collected in the vicinity of Leuven (Belgium) and taken to the lab (KU Leuven), where newly emerged females and males were sampled, marked individually, and kept in plastic boxes for at least a week before being used in the mating trials. Focal males were paired with females and males from different nests and subjected to five different conditions: (I) alive, (II) dead, (III) CHCs washed, (IV) CHCs partially returned, and (V) CHCs from the opposite sex. We videotaped the interactions for 10 min and analysed the duration and different behavioural interactions of the focal male. Our results indicate that CHCs may be used by males as cues to recognise a potential mating partner in P. dominula, since the focal males displayed specific courtship behaviours exclusively toward females. Although we cannot exclude that visual cues could also be used in combination with the chemical ones, we empirically demonstrate that CHCs may be important to convey sexual information at close range in mating systems, allowing fast decisions toward potential sexual partners or rivals.

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ABSTRACT Species of the scarab beetle genus Liogenys are potential pests to several crops in Brazil. This study aimed to describe the antennal sensilla of Liogenys suturalis (Blanchard, 1851). Adults were collected in a pasture area in Bálsamo, São Paulo state, Brazil, using a light trap. The antennae were dissected and images of the antennal sensilla were obtained using a scanning electron microscope. Sensilla ampulacea (pores), s. auricilica, s. basiconica, s. placodea, and s. trichodea are present in the lamellae. The antenna of females have 4399 sensilla, of which 3671 (83.5%) are s. placodea, 422 (9.5%) s. coeloconica, and 306 (6.9%) s. auricilica. The antennae of males have 4039 sensilla, of which 3117 (77.1%) are s. placodea, 353 (8.7%) s. coeloconica, and 569 (14.1%) s. auricilica. The antennal sensilla of the genus Liogenys have been described for the first time.

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ABSTRACT Antennal sensilla are important functional elements of sensory systems in insects. This study aimed to determine the morphology and structure of the sensilla of two species of the genus Hoplopyga. Adults of Hoplopyga liturata (Olivier, 1789) were collected in traps with sugarcane juice as an attractant. Thereafter, larvae of Hoplopyga albiventris (Gory and Percheron, 1833) were collected in mounds of termites (Cornitermes cumulans (Kollar, 1832) Isoptera). Then, they were reared in the laboratory for adult observations. Antennae of H. liturata and H. albiventris have sensilla chaetica, trichodea, placodea (type I and II), coeloconica (type I and II), and ampullacea (or pore). Females of H. liturata have a total of about 10657 sensilla and males have about 12512, whereas females of H. albiventris have about 16490 sensilla and the males 24565 sensilla. Sensilla placodea are predominant in the antenna of males and females of both species.

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The dominance hierarchy in primitively eusocial insect societies has been shown to be mainly regulated through aggressive interactions. Females that are generally more dominant stand out and occupy the queen position, meaning that they monopolize reproduction while others perform other tasks. Chemical communication is important for maintaining social cohesion. Cuticular hydrocarbons are recognized as the main molecules responsible for mediating social interactions, especially nestmate recognition and queen signalling. Many highly eusocial groups have been studied in recent years, but primitively eusocial groups, which are key to understanding the evolution of social behavior, remain unexplored. In this study, we investigated the connection between cuticular hydrocarbons in females expressed in different social contexts in the primitively eusocial wasp Mischocyttarus cerberus. Colonies in two different ontogenetic phases, pre- and post-worker emergence, were used. We observed and categorized behavioral interactions between individual females and collected all individuals in a nest to obtain information on size, ovary activation and chemical composition. Furthermore, we conducted experiments in which the alpha (dominant) females were removed from nests to produce a new dominance hierarchy. We found that females in different hierarchical positions had small chemical difference corresponding with ovary activity. Our results support the hypothesis that cuticular hydrocarbons are associated with social context in this primitively eusocial species, with some compounds being associated with hierarchical position and ovarian activity.

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Although chemical interactions play an essential role in lizard social behavior, the chemical composition of the femoral gland secretions that many lizards use for communication is known for only a few species, mainly European Lacertids. The tegu lizard, Salvator merianae, is the only species of the Teiidae family for which there is available information on lipids in femoral secretions, but only for captive bred males from Argentina. Here, based on mass spectra obtained by GC-MS, we found 69 lipophilic compounds in femoral gland secretions of wild males S. merianae from Brazil, including cholesterol and high amounts of saturated fatty acids (mainly hexadecanoic and octadecanoic). We found contrasting differences between wild and captive-bred males, which lack cholesterol but present high amount of 9,12-octadecadienoic acid. These within-species differences between wild and captive lizards strongly suggest the important influence of different diets on the chemical composition of the femoral gland secretion and suggest caution when interpreting results from captive animals, even in the same species.

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The weevil Metamasius spinolae (Gyllenhal) is the most important insect pest of cultivated prickly pear in Mexico. A previous work reported that the pheromone of this weevil species was composed by three components. In this study, we reinvestigated the aggregation pheromone of M. spinolae using gas chromatography-electroantennography and gas chromatography-mass spectrometry to locate and identify new potential pheromonal compounds. The behavioral activity of identified compounds was evaluated in laboratory and field trials. Metamasius spinolae males released four compounds: 2-methyl-4-heptanone, 6-methyl-2-hepten-4-one, 2-methyl-4-octanone, and 2-hydroxy-2-methyl-4-heptanone. In the laboratory assays, depending on the concentration, the compounds were attractive, neutral, or repellent to M. spinolae. Field evaluation showed that traps baited with 2-hydroxy-2-methyl-4-heptanone singly or in most of the binary or tertiary blends where this compound was present captured a higher number of M. spinolae compared to live males and the other compounds identified. In conclusion, our results indicate that 2-hydroxy-2-methyl-4-heptanone is the main component of the aggregation pheromone of M. spinolae. We suggest that this compound should be used for developing a monitoring or a mass-trapping system for M. spinolae.

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Many hymenopteran parasitoids are known as biocontrol agents, such as Anisopteromalus calandrae (Howard) (Hymenoptera: Pteromalidae), which is known to parasitize larvae and pupae of coleopteran pests including Lasioderma serricorne (Fabricius) (Coleoptera: Ptinidae). The success of these parasitoids is related to their searching ability, which is mediated through chemical stimuli of the habitat, food, and the progeny of the host itself. This study aimed to assess the chemotaxic responses of A. calandrae comparing the reproductive state of the insects and the experience of wasp females, to different development stages (larvae and pupae) and the presence or absence of the host diet. The chemotaxic responses of A. calandrae individuals at 2 to 4 days old were assessed in a "Y" type olfactometer. Virgin and paired females (without and with previous experience of parasitism) were exposed to larvae of last instar contrasted with pupae and to the diet of L. serricorne. Both virgin and mated males were tested only for diet. Virgin females showed a preference for the diet in contrast to the larvae and to the pupae in contrast to the diet. Paired females without experience choose larvae over diet and made no distinction between pupae and diet. Experienced mated females showed preference for the host to which it had access before, instead of any other alternative option, indicating that there may be changes in the preference through learning.

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Abstract The genus Cyclocephala is common in Brazil (Coleoptera, Scarabaeidae, Dynastinae). The adults of some species are important pollinators, and the larvae develop in the soil, feed on organic matter, and contribute to nutrient cycle, but immatures of some species feed on plant roots, and some were registered causing damage in crops. The mating process of some phytophagous scarab beetles has a chemical recognition step, and the antenna is the main structure involved in the detection of odorants associated with insect communication. In the present study the mating behavior, life cycle, and antennal sensilla of C. putrida are described. The study was conducted at the Universidade Estadual de Mato Grosso do Sul, Cassilândia, Brazil. Adults were collected by a light trap installed from January 2016 to December 2017 and were taken to the laboratory for studies. Adults swarms are brief and were registered from January to February, and specimens were mostly collected at 20:00 to 22:00h. Chemical recognition may occur at least during one of the mating steps, during which the couple kept their antennae moving and the lamellae open, while females select males. In laboratory, the mating process lasted 7.5 minutes on average. The antennae of females have about 3399 sensilla and males about 4229 sensilla. Sensilla placodea types I, II, and III are the most abundant, and sensilla ampullacea, basiconica, and coeloconica are also present. The embryonic period lasted 16.0 days; first, second and third instars lasted 16.0, 48.3, and 165.3 days, respectively. The pupal period lasted 24.0 days. The period between egg deposition and adult emergency is about 271.5 days.

Resumo O gênero Cyclocephala é comum no Brasil (Coleoptera, Scarabaeidae, Dynastinae). Os adultos de algumas espécies são importantes polinizadores, e a larva desenvolve-se no solo, alimenta-se de matéria orgânica e contribui para a ciclagem de nutrientes, mas imaturos de algumas espécies alimentam-se de raízes de plantas, e alguns são registrados causando danos em plantas cultivadas. O processo de cópula de algumas espécies de Scarabaeidae fitófagos, apresentam reconhecimento químico, e nas antenas aparecem várias estruturas responsáveis pela detecção dos odores envolvidos na comunicação. No presente trabalho o comportamento de cópula, ciclo de vida e sensilas antenais de Cyclocephala putrida são descritos. O estudo foi conduzido na Universidade Estadual de Mato Grosso do Sul, Cassilândia, Brasil. Adultos foram coletados com armadilha luminosa instalada de Janeiro de 2016 a Dezembro de 2017, e levados para laboratório para estudos. Os adultos revoam por curto período de janeiro a fevereiro, e os espécimes foram coletados em maior quantidade das 20:00 às 22:00 h. O reconhecimento químico possivelmente ocorre durante as etapas que envolvem o comportamento de cópula, no qual o casal mantém as antenas em movimento e as lamelas abertas e as fêmeas selecionam os machos. Em laboratório a cópula dura 7,5 minutos em média. As antenas das fêmeas possuem 3399 sensilas e os machos 4229 sensilas, e as sensilas placódeas dos tipos I, II e III, foram as mais abundantes e sensilas ampuláceas, basicônicas e coelocônicas também estão presentes. O estágio de ovo durou 16,0 dias; o primeiro, segundo e terceiro instar duraram 16,0, 48,3 e 165,3 dias, respectivamente. O período pupal durou 24,0 dias. O período entre deposição dos ovos e emergência dos adultos é de 271,5 dias em média.

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Although chemical interactions play an essential role in lizard social behavior, the chemical composition of the femoral gland secretions that many lizards use for communication is known for only a few species, mainly European Lacertids. The tegu lizard, Salvator merianae, is the only species of the Teiidae family for which there is available information on lipids in femoral secretions, but only for captive bred males from Argentina. Here, based on mass spectra obtained by GC-MS, we found 69 lipophilic compounds in femoral gland secretions of wild males S. merianae from Brazil, including cholesterol and high amounts of saturated fatty acids (mainly hexadecanoic and octadecanoic). We found contrasting differences between wild and captive-bred males, which lack cholesterol but present high amount of 9,12-octadecadienoic acid. These within-species differences between wild and captive lizards strongly suggest the important influence of different diets on the chemical composition of the femoral gland secretion and suggest caution when interpreting results from captive animals, even in the same species.

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Communication between plants and nocturnal pollinators in low light conditions is mainly guided by floral scents, which is well documented for plants pollinated by bats, moths, and beetles. Just recently, nocturnal bees have been added to the list of pollinators known to respond to floral scents of their host plants. Little is known about the floral scent chemistry of plants visited and pollinated by nocturnal bees. Among these plants are economically important fruit crops of the family Myrtaceae. We aimed to analyze the nocturnal floral scent profiles of 10 species of Myrtaceae (only diurnal P. cattleianum was sampled after sunrise) and address the following questions: i) What are the main floral scent compounds emitted by the species? ii) Are the floral scent profiles similar to those described for other species pollinated by nocturnal bees? Floral scents were collected by dynamic headspace and analyzed by GC-MS (gas chromatography - mass spectrometry). The total amount of scent trapped ranged from 74 ng/flower/hour for Syzygium malaccense to 7556 ng/flower/hour for Eugenia dysenterica. A total of 46 floral scent compounds were detected in the samples with the most abundant compounds being the aromatics benzaldehyde, benzyl alcohol, 2-phenylethanol, methyl salicylate, 2-phenylethyl acetate, and benzyl acetate; the aliphatic compound 1-octanol; and the monoterpene linalool. The different species exhibited different relative scent patterns. Overall, the nocturnal scents of the studied species of Myrtaceae are dominated by aromatic compounds, which is in contrast to the scent profiles described for other plants pollinated by nocturnal bees.

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Several fish species trigger defensive behavioral responses when exposed to chemical cues that indicate predation risk. In these situations, physiological adjustments are also necessary to prepare the organism for a defensive response and increase survival odds. Chemical cues may be derived from predator odor or injured conspecifics. However, little is known about the effects of both cues combined. Therefore, our study evaluated the combined effects of predator odor (PO) and conspecific alarm substance (CAS) on the anti-predatory responses of the pearl cichlid (Geophagus brasiliensis). We set 4 experimental conditions 1) PO + CAS; 2) PO + Distilled Water (DW); 3) DW + CAS; and 4) DW + DW (negative control). Fish exposed to DW + CAS had values of ventilation rate and feeding latency significantly higher than when exposed to the other conditions, which yielded similar responses for both variables. Our data show that the combination of PO + CAS interfered with pearl cichlid behavior and physiology since it abolished CAS defensive responses. These results show that CAS plays an important role on the defensive responses of pearl cichlids, while PO does not, given that fish did not respond to PO by itself. Our findings point to different cue-specific strategies in pearl cichlids when dealing with different chemical cues that indicate predation risk.

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Abstract: When suitable, adults of Scarabaeidae usually form swarms to find food and breeding sites. The steps of mating behavior can be mediated by chemical communication, and antennal sensilla are released volatiles detection structures, as sexual pheromones. In present work the mating behavior and the antennal sensilla of Anomala inconstans Burmeister, 1844 are described. The study was conducted at the Universidade Estadual de Mato Grosso do Sul, Cassilândia, Brazil from March 2015 to December 2017. Adults were collected through a light trap and taken to the laboratory for studies. Field and laboratory observations provided data for the description of the steps of mating behavior. Adults swarms were registered from September to November 2015 at 05:30 pm to 00:00 am. Females display a calling behavior from 05:25 pm to 08:00 pm, in which they rub their posterior legs against their abdomen, and after a few minutes males are able to locate them. In laboratory, the mating process lasted 20.4 minutes on average, and the possibility of chemical communication between adults was here discussed. The antennae of the species have trichoid, chaetica, placoid types I, II and III, and coeloconic types I and II sensilla. Placoid sensilla are the most abundant and females have more sensilla than males.

Resumo: Em condições adequadas os adultos de Scarabaeidae geralmente realizam revoadas em busca de alimento e áreas de reprodução. As etapas relacionadas ao comportamento de cópula podem ser intermediadas por comunicação química, e os sensilos antenais são as estruturas que detectam os voláteis como os feromônios sexuais. No presente trabalho o comportamento de cópula e os sensilos antenais de Anomala inconstans Burmeister, 1844 são descritos. Os estudos foram conduzidos na Universidade Estadual de Mato Grosso do Sul, Cassilândia, de março de 2015 a dezembro de 2017. Adultos foram coletados com armadilha luminosa e conduzidos para laboratório para estudos. Observações de campo e de laboratório permitiram a descrição das etapas do comportamento de cópula. Os adultos revoaram de setembro a novembro de 2015 das 17:30h as 24:00h. As fêmeas apresentam o comportamento de chamamento das 17:25h as 20:00h, no qual atrita o terceiro par de pernas no abdome e, transcorridos alguns minutos, os machos as localizam. Em laboratório a cópula durou em média 20,4 minutos, sendo verificada a possibilidade de comunicação química entre os adultos. Nas antenas foram encontrados sensilos tricódios, chaéticos, placódios dos tipos I, II e III, e coelocônicos tipo I e II. Os sensilos placódios são os mais abundantes, e as fêmeas possuem mais sensilos do que os machos.