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Olfaction, one of the most important sensory systems governing insect behavior, is a possible target for pest management. Therefore, in this study, we analyzed the antennal transcriptome of the cowpea beetle, Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae: Bruchinae), which is a major pest of stored pulses and legumes. The de novo antennal RNA-seq assembly results identified 17 odorant, 2 gustatory, and 10 ionotropic receptors, 1 sensory neuron membrane protein, and 12 odorant-binding and 7 chemosensory proteins. Moreover, differential gene expression analysis of virgin male and female antennal samples followed by qRT-PCR revealed 1 upregulated and 4 downregulated odorant receptors in males. We also performed homology searches using the coding sequences built from previously proposed amino acid sequences derived from genomic data and identified additional chemosensory-related genes.

The cilium, the sensing centre for the cell, displays an extensive repertoire of receptors for various cell signalling processes. The dynamic nature of ciliary signalling indicates that the ciliary entry of receptors and associated proteins must be regulated and conditional. To understand this process, we studied the ciliary localisation of the odour-receptor coreceptor (Orco), a seven-pass transmembrane protein essential for insect olfaction. Little is known about when and how Orco gets into the cilia. Here, using Drosophila melanogaster, we show that the bulk of Orco selectively enters the cilia on adult olfactory sensory neurons in two discrete, one-hour intervals after eclosion. A conditional loss of heterotrimeric kinesin-2 during this period reduces the electrophysiological response to odours and affects olfactory behaviour. We further show that Orco binds to the C-terminal tail fragments of the heterotrimeric kinesin-2 motor, which is required to transfer Orco from the ciliary base to the outer segment and maintain within an approximately four-micron stretch at the distal portion of the ciliary outer-segment. The Orco transport was not affected by the loss of critical intraflagellar transport components, IFT172/Oseg2 and IFT88/NompB, respectively, during the adult stage. These results highlight a novel developmental regulation of seven-pass transmembrane receptor transport into the cilia and indicate that ciliary signalling is both developmentally and temporally regulated., PLoS Genetics, 17 (8), ISSN:1553-7390, ISSN:1553-7404

Reconfigurable antennas have received much attention in RF energy harvesting models owing to their selectivity for operating frequency and polarization. The characteristic of having frequency selectivity and polarization selectivity can be termed as frequency diversity and polarization diversity, respectively. This paper investigates a rectenna device with a new proposed topology in order to eliminate coupling between input and output lines and increase the rectification efficiency with the use of single feed hybrid reconfigurable antenna, switch between 28GHz and 38GHz frequency. Moreover, it is designed to charge a rechargeable battery of 1watt(W). The Reconfiguration mechanism is realized by electronically controlling different states of Switches. PIN Diode (as RLC Equivalent circuit) is used as a switch for ON/OFF states. This antenna mainly comprises rectangular shaped patches (28GHz and 38GHz) with Triango-Truncated edge at the corners. Eighteen PIN Diodes are placed symmetrically throughout the antenna presenting as, S1 & S2 for frequency reconfiguration, S3 to S6 & S7 to S10 connects Triango Truncated edge at the corners for polarization reconfiguration, and for radiation pattern reconfiguration at S11 to S14 & S15 to S18 has been used. The proposed antenna model is capable of simultaneously changing, the radiation patterns as clock and anti-clockwise directions at ±90-degree shift in E and H planes, circularly polarized (CP) states among, Linear Polarization (LP), Right Hand Circularly Polarization (RHCP), and Left Hand Circularly Polarization (LHCP). The current design describes using single antenna for energy harvesting and 5G mobile communication application. This would lead to higher output currents, leading to the ability to efficiently charge a wide variety of batteries. A fully functional prototype has been designed, fabricated and its compound reconfiguration characteristics have been validated for simulated and measured results. For validation of results, the experimental results and the simulation results from the proposed mathematical model were made into comparison, and excellent correlation between the measured and simulated results was obtained.

We developed a facile detection method of spermine based on the fluorescence (FL) quenching of the ciprofloxacin-Tb3+ complex, which shows astrong green emission. Ciprofloxacin (CP) makes efficient bondings to Tb3+ ion as a linker molecule through carboxylic and ketone groups to form a kind of lanthanide coordination polymer. The addition of spermine that competes with Tb3+ ions for the interaction with CP due to its positive charge brings about weakened coordination linkage of CP and Tb3+. The probe exhibited high sensitivity, selectivity, and good linearity in the range of 2–180 μM with a low limit of detection of 0.17 μM. Moreover, we applied this method on the paper strip test (PST), along with the integration of a smartphone and Arduino-based device. The practical reliability of the developed probe was evaluated on human serum samples with acceptable analytical results.

Phytoplankton play a central role in our ecosystems, they are responsible for nearly 50 percent of the global primary productivity and major drivers of macro-elemental cycles in the ocean. Phytoplankton are constantly subjected to stressors, some natural such as nutrient limitation and some manmade such as oil spills. With increasing oil exploration activities in coastal zones in the Gulf of Mexico and elsewhere, an oil spill during nutrient-limited conditions for phytoplankton growth is highly likely. We performed a multifactorial study exposing the diatom Phaeodactylum tricornutum (UTEX 646) to oil and/or dispersants under nitrogen and silica limitation as well as co-limitation of both nutrients. Our study found that treatments with nitrogen limitation (-N and–N-Si) showed overall lower growth and chlorophyll a, lower photosynthetic antennae size, lower maximum photosynthetic efficiency, lower protein in exopolymeric substance (EPS), but higher connectivity between photosystems compared to non-nitrogen limited treatments (-Si and +N+Si) in almost all the conditions with oil and/or dispersants. However, certain combinations of nutrient limitation and oil and/or dispersant differed from this trend indicating strong interactive effects. When analyzed for significant interactive effects, the–N treatment impact on cellular growth in oil and oil plus dispersant conditions; and oil and oil plus dispersant conditions on cellular growth in–N-Si and–N treatments were found to be significant. Overall, we demonstrate that nitrogen limitation can affect the oil resistant trait of P. tricornutum, and oil with and without dispersants can have interactive effects with nutrient limitation on this diatom.

Fossil freshwater carideans are very rare worldwide. Here, we present new taxonomic remarks about Beurlenia araripensis from the Early Cretaceous laminated limestones of the Crato Formation, Araripe Basin, northeastern Brazil. We analyzed five fossil samples, testing the morphological variations such as, rostrum with 5 to 14 supra-rostral spines and 2 to 3 sub-rostral spines, which appears as serrate for Caridea. This variation demonstrates a morphologic plasticity also seen in extant species of the group, such as those of the genera Macrobrachium and Palaemon.

We compiled the records for the genus Salvatoria from Brazilian coastal and oceanic habitats, collected by several projects along the years. Here we present 12 species, eight of which already reported–S. breviarticulata comb. nov., S. clavata, S. euritmica, S. heterocirra, S. limbata, S. longiarticulata comb. nov., S. neapolitana and S. cf. nitidula–with comments regarding the confidence of some of these records. We also describe three new species, S. marielleae n. sp. and Salvatoria nitiduloides n. sp., based on material from Fernando de Noronha and Trindade islands, off the Northeastern Brazilian coast, and S. ypsiloides n. sp., from Fernando de Noronha and also, Campos Basin, off Southeastern Brazilian coast, in depths down to 970 m. Finally, we report a probably undescribed species, Salvatoria sp., represented by only one specimen lacking median antenna, preventing us to proceed with further identification properly. A dichotomous identification key and a comparative table with morphological data of specimens belonging to these species are also provided.

American trypanosomiasis, or Chagas disease, is transmitted by both domestic and sylvatic species of Triatominae which use sensory cues to locate their vertebrate hosts. Among them, odorants have been shown to play a key role. Previous work revealed morphological differences in the sensory apparatus of different species of Triatomines, but to date a comparative functional study of the olfactory system is lacking. After examining the antennal sensilla with scanning electronic microscopy (SEM), we compared olfactory responses of Rhodnius prolixus and the sylvatic Rhodnius brethesi using an electrophysiological approach. In electroantennogram (EAG) recordings, we first showed that the antenna of R. prolixus is highly responsive to carboxylic acids, compounds found in their habitat and the headspace of their vertebrate hosts. We then compared responses from olfactory sensory neurons (OSNs) housed in the grooved peg sensilla of both species, as these are tuned to these compounds using single-sensillum recordings (SSRs). In R. prolixus, the SSR responses revealed a narrower tuning breath than its sylvatic sibling, with the latter showing responses to a broader range of chemical classes. Additionally, we observed significant differences between these two species in their response to particular volatiles, such as amyl acetate and butyryl chloride. In summary, the closely related, but ecologically differentiated R. prolixus and R. brethesi display distinct differences in their olfactory functions. Considering the ongoing rapid destruction of the natural habitat of sylvatic species and the likely shift towards environments shaped by humans, we expect that our results will contribute to the design of efficient vector control strategies in the future., Author summary An estimated eight million people worldwide are infected with American trypanosomiasis, also known as Chagas disease, whose causative agent is the parasite Trypanosoma cruzi. Over a hundred species of insects belonging to the Tritatomine subfamily are vectors of the disease, as they spread T. cruzi through their feaces. Several studies have highlighted the importance of olfaction for host-seeking behavior in these insects, which enables them to locate their vertebrate hosts and to obtain their vital blood meal. Vector control strategies have been the most efficient policy to combat the spread of Chagas disease by triatomine insects. However, recent changes in the natural habitats of these insects challenge the efficacy of these strategies, as species so far thought to be exclusive to sylvatic environments are now frequently found in peridomestic areas. In this context, understanding how triatomines with different distributions detect odors to locate their hosts and choose their habitats is highly relevant. In this study, we compare the olfactory system of the widely distributed Rhodnius prolixus and a sylvatic sibling Rhodnius brethesi at a morphological and functional level. We reveal that detection of host and habitat volatiles share many similarities, but also exhibit pronounced differences between species.

The giant sugarcane borer Telchin licus (Drury, 1773) (Lepidoptera: Castniidae) is a day-flying moth pest of sugarcane, pineapples and bananas. To better understand the chemical communication in this species, we examined the morphology of its olfactory system and the chemical composition of its body parts. The ventral surface of the clubbed antennae of T. licus has six morphological types of sensilla: sensilla trichodea, basiconica, chaetica, squamiforma, coeloconica, and auricillica. The telescopic ovipositor shows no evidence of a sexual gland, or female-specific compounds. On the other hand, the midleg basitarsus of males releases (E,Z)-2,13-octadecadienol and (Z,E)-2,13-octadecadienol, which are electroantennographically active in both sexes. These compounds are known female sex pheromones in the Sesiidae family and are male-specific compounds in another castniid moth, although further investigations are necessary to elucidate their ecological role in the Castniidae family.

Pathogens may manipulate their human and mosquito hosts to enhance disease transmission. Dengue, caused by four viral serotypes, is the fastest-growing transmissible disease globally resulting in 50–100 million infections annually. Transmission of the disease relies on the interaction between humans and the vector Aedes aegypti and is largely dependent on the odor-mediated host seeking of female mosquitoes. In this study, we use activity monitors to demonstrate that dengue virus-1 affects the locomotion and odor-mediated behavior of Ae. aegypti, reflecting the progression of infection within the mosquito. Mosquitoes 4–6 days post-infection increase locomotion, but do not alter their odor-driven host-seeking response. In contrast, females 14–16 days post-infection are less active, yet more sensitive to human odors as assessed by behavioral and electrophysiological assays. Such an increase in physiological and behavioral sensitivity is reflected by the antennal-specific increase in abundance of neural signaling transcripts in 14 days post-infection females, as determined by transcriptome analysis. This suggests that the sensitivity of the mosquito peripheral olfactory system is altered by the dengue virus by enhancing the overall neural responsiveness of the antenna, rather than the selective regulation of chemosensory-related genes. Our study reveals that dengue virus-1 enhances vector-related behaviors in the early stages post-infection that aid in avoiding predation and increasing spatial exploration. On the other hand, at the later stages of infection, the virus enhances the host-seeking capacity of the vector, thereby increasing the risk of virus transmission. A potential mechanism is discussed., Author summary The mosquito Aedes aegypti is a major urban vector for human pathogens, including dengue, the most rapidly-spreading infectious disease globally. We show that one of the four strains of the dengue virus differentially, and inversely, affects the locomotion and odour-mediated behaviour of female Aedes aegypti. During the early stages after infection, female mosquitoes show an increased locomotion activity suggesting that the virus likely promotes mosquito dispersion and increases its spatial exploration. In contrast, in the later infective stages, dengue infection modulates the mosquito’s host-seeking capacity, by enhancing the physiological and behavioural sensitivity to human odors, thus increasing the risk of virus transmission. At this stage of infection, neural signalling gene expression is enhanced, providing a mechanism for the increased sensitivity to human odor, while genes involved in chemosensation and neuromodulation are likely playing a secondary role. A better understanding of alterations of mosquito host-seeking behavior upon pathogen infection will contribute to the development of novel control strategies against vector borne diseases.

Mechanisms that control movements range from navigational mechanisms, in which the animal employs directional cues to reach a specific destination, to search movements during which there are little or no environmental cues. Even though most real-world movements result from an interplay between these mechanisms, an experimental system and theoretical framework for the study of interplay of these mechanisms is not available. Here, we rectify this deficit. We create a new method to stimulate the olfactory system in Drosophila or fruit flies. As flies explore a circular arena, their olfactory receptor neuron (ORNs) are optogenetically activated within a central region making this region attractive to the flies without emitting any clear directional signals outside this central region. In the absence of ORN activation, the fly’s locomotion can be described by a random walk model where a fly’s movement is described by its speed and turn-rate (or kinematics). Upon optogenetic stimulation, the fly’s behavior changes dramatically in two respects. First, there are large kinematic changes. Second, there are more turns at the border between light-zone and no-light-zone and these turns have an inward bias. Surprisingly, there is no increase in turn-rate, rather a large decrease in speed that makes it appear that the flies are turning at the border. Similarly, the inward bias of the turns is a result of the increase in turn angle. These two mechanisms entirely account for the change in a fly’s locomotion. No complex mechanisms such as path-integration or a careful evaluation of gradients are necessary., Author summary The strategy an animal employs to explore the environment and to find and return to the location where it has previously found food or mates is an important part of its behavior. In nature, animals have incomplete information about their environment, and must use this incomplete information to navigate. In most laboratory experiments, there is usually clear directional information making it difficult to infer an animal’s real strategy from laboratory behavioral experiments. In this study, we devise a new behavioral task wherein we remotely activate olfactory neurons when fruit flies are in a given location. This activation makes a given location attractive to the flies without providing any directional information and allows us to assess how flies navigate under these conditions. We find that flies navigate towards the activated location using two simple mechanisms: First, its speed in the activated region and its turn rate is much lower than it is elsewhere. Second, at the boundary of the odor-zone, its speed decreases dramatically and its turns become much sharper. Essentially, these simple mechanisms appear to be extremely robust.

Social experience, particularly aggression, is considered a major determinant of consistent inter-individual behavioural differences between animals of the same species and sex. We investigated the influence of pre-adult aggressive experience on future behaviour in male, last instar nymphs of the cricket Gryllus bimaculatus. We found that aggressive interactions between male nymphs are far less fierce than for adults in terms of duration and escalation. This appears to reflect immaturity of the sensory apparatus for releasing aggression, rather than the motor system controlling it. First, a comparison of the behavioural responses of nymphs and adults to mechanical antennal stimulation using freshly excised, untreated and hexane-washed antennae taken from nymphs and adults, indicate that nymphs neither respond to nor produce sex-specific cuticular semiochemicals important for releasing aggressive behaviour in adults. Second, treatment with the octopamine agonist chlordimeform could at least partially compensate for this deficit. In further contrast to adults, which become hyper-aggressive after victory, but submissive after defeat, such winner and loser effects are not apparent in nymphs. Aggressive competition between nymphs thus appears to have no consequence for future behaviour in crickets. Male nymphs are often attacked by adult males, but not by adult females. Furthermore, observations of nymphs raised in the presence, or absence of adult males, revealed that social subjugation by adult males leads to reduced aggressiveness and depressed exploratory behaviour when the nymphs become adult. We conclude that social subjugation by adults during pre-adult development of nymphs is a major determinant of consistent inter-individual behavioural differences in adult crickets.

Nowadays, with the significant integration of various renewable energy, hybrid alternating current/ voltage source converter based high voltage direct current (AC/VSC-HVDC) system integrated with doubly-fed induction generator (DFIG) has achieved rapidly development in smart grid. A proper control system design for hybrid AC/VSC-HVDC system plays a very crucial role for a reliable and effective power transmission. Hence, this paper designs a novel cooperative beetle antenna search (CBAS) algorithm for optimal coordinated control of hybrid AC/VSC-HVDC system integrated with DFIG. Compared with original beetle antennae search (BAS) algorithm, CBAS algorithm can significantly improve searching efficiency via an efficient cooperation with a group of multiple beetles instead of a single beetle. Particularly, CBAS algorithm can effectively escape from local optimums thanks to its dynamic balance mechanism, which can maintain appropriate trade-off between global exploration and local exploitation. Moreover, three case studies are undertaken to validate the effectiveness and superiorities and effectiveness of CBAS algorithm compared against that of other traditional meta-heuristic algorithms. Especially, the average results of fitness function acquired by CBAS algorithm is merely 46.05%, 41.18%, and 47.82% of that of PSO, GA, and BAS algorithm, respectively.

PubMed ID: 32392253, In this work, a novel sensor based on printed circuit board (PCB) microstrip rectangular patch antenna is proposed to detect different ratios of ethanol alcohol in wines and isopropyl alcohol in disinfectants. The proposed sensor was designed by finite integration technique (FIT) based high-frequency electromagnetic solver (CST) and was fabricated by Proto Mat E33 machine. To implement the numerical investigations, dielectric properties of the samples were first measured by a dielectric probe kit then uploaded into the simulation program. Results showed a linear shifting in the resonant frequency of the sensor when the dielectric constant of the samples were changed due to different concentrations of ethanol alcohol and isopropyl alcohol. A good agreement was observed between the calculated and measured results, emphasizing the usability of dielectric behavior as an input sensing agent. It was concluded that the proposed sensor is viable for multipurpose chemical sensing applications. © 2020 Karatepe et al.

Olfaction plays vital roles in the survival and reproduction of insects. The completion of olfactory recognition requires the participation of various complex protein families. However, little is known about the olfactory-related proteins in Semiothisa cinerearia Bremer et Grey, an important pest of Chinese scholar tree. In this study, we sequenced the antennal transcriptome of S. cinerearia and identified 125 olfactory-related genes, including 25 odorant-binding proteins (OBPs), 15 chemosensory proteins (CSPs), two sensory neuron membrane proteins (SNMPs), 52 odorant receptors (ORs), eight gustatory receptors (GRs) and 23 ionotropic receptors (IRs). BLASTX best hit results and phylogenetic analyses indicated that these genes were most identical to their respective orthologs from Ectropis obliqua. Further quantitative real-time PCR (qRT-PCR) analysis revealed that three ScinOBPs and three ScinORs were highly expressed in male antennae, while seven ScinOBPs and twelve ScinORs were female-specifically expressed. Our study will be useful for the elucidation of olfactory mechanisms in S. cinerearia.

Quantitative real-time polymerase chain reaction (qPT-PCR) is commonly used to analyze gene expression, however, the accuracy of the normalized results is affected by the expression stability of reference genes. Holotrichia oblita (Coleoptera: Scarabaeidae) causes serious damage to crops. Reliable reference genes in H. oblita are needed for qRT-PCR analysis. Therefore, we evaluated 13 reference genes under biotic and abiotic conditions. RefFinder provided a comprehensive stability ranking, and geNorm suggested the optimal number of reference genes for normalization. RPL13a and RPL18 were the most suitable reference genes for developmental stages, tissues, and temperature treatments; RPL13a and RPS3 were the most suitable for pesticide and photoperiod treatments; RPS18 and RPL18 were the most suitable for the two sexes. We validated the normalized results using odorant-binding protein genes as target genes in different tissues. Compared with the selected suitable reference genes, the expression of OBP1 in antennae, abdomen, and wings, and OBP2 in antennae and wings were overestimated due to the instability of ACTb. These results identified several reliable reference genes in H. oblita for normalization, and are valuable for future molecular studies.

Euplatypus parallelus (F.) (Coleoptera: Curculionidea) is the most destructive cosmopolitan insect pest of the Platypodinae. Pheromone-based luring agents are used currently in controlling bark beetle. Antennae are the primary insect organs sensing volatiles of host trees and pheromones of pioneer males. We studied the external morphology of antennae and the type, distribution, and the number of the beetle sensilla. Our results show E. parallelus have a geniculate antenna composed of 6 segments, namely the scape, 4-segmented funicle and club. Ninety-seven percent of the antennal sensors were distributed in the club, and 3% were distributed in the scape and funicle. 6 types of sensilla on the antennae were found, including sensilla trichodea (subtypes: STI, STII and STIII), sensilla basiconica (subtypes: SBI, SBII, SBIII and SBIV), sensilla chaetica (subtypes: SChI, SChII and SChIII), as well as sensilla coeloconica, sensilla campaniform and sensilla furcatea. There was no significant difference in the type, distribution and number of sensilla in males and females. No significant difference in the shape and distribution of antennae was found between sexes, but the length of antennae and the number of SChI, SChII, STI, SBI, SBIII and SBIV were significantly larger in females than males. We revealed the external cuticular structure of the antennae in E. parallelus, which can be used to guide future electrophysiological investigations to understand the ability of this beetle to detect semiochemicals.

The lady beetle Hippodamia variegata is an important biocontrol agent of many aphids. In this study, the fine morphology of antennae as well as the typology, morphology and distribution of antennal sensilla were comprehensively examined by scanning electron microscopy. The antennal morphology of female and male are similar and consist of the scape, pedicel, and nine flagellomeres. No significant difference was detected in the length of each segment between two sexes, while the male antennae are much stronger than females. In total, six types of sensilla can be defined on antenna, including Bohm bristle, sensilla chaetica (with three subtypes), sensilla basiconica (with three subtypes), sensilla trichodea, sensilla placodea and sensilla coeloconica. It is worth noting that sensilla chaetica III distributed only on the fixed position of male antennae. In addition, the functional morphology of antennae of H. variegata were compared with other lady beetles from multiple perspectives. Specially, the function of sensilla were also discussed according to their morphology, location and information from previous studies.

The communication and reproduction of insects are driven by chemical sensing. During this process, chemical compounds are transported across the sensillum lymph to the sensory neurons assisted by different types of soluble binding proteins: odorant-binding proteins (OBPs); chemosensory proteins (CSPs); some members of ML-family proteins (MD-2 (myeloid differentiation factor-2)-related Lipid-recognition), also known as NPC2-like proteins. Potential transcripts involved in chemosensing were identified by an in silico analysis of whole-body female and male transcriptomes of the parasitic wasp Diachasmimorpha longicaudata. This analysis facilitated the characterization of fourteen OBPs (all belonging to the Classic type), seven CSPs (and two possible isoforms), and four NPC2-like proteins. A differential expression analysis by qPCR showed that eleven of these proteins (CSPs 2 and 8, OBPs 2, 3, 4, 5, 6, 9, 10, and 11, and NPC2b) were over-expressed in female antenna and two (CSP 1 and OBP 12) in the body without antennae. Foraging behavior trials (linked to RNA interference) suggest that OBPs 9, 10, and 11 are potentially involved in the female orientation to chemical cues associated with the host. OBP 12 seems to be related to physiological processes of female longevity regulation. In addition, transcriptional silencing of CSP 3 showed that this protein is potentially associated with the regulation of foraging behavior. This study supports the hypothesis that soluble binding proteins are potentially linked to fundamental physiological processes and behaviors in D. longicaudata. The results obtained here contribute useful information to increase the parasitoid performance as a biological control agent of fruit fly pest species. Instituto de Genética Fil: Wulff, Juan Pedro. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética. Laboratorio de Insectos de Importancia Económica; Argentina. Fil: Wulff, Juan Pedro. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Segura, Diego Fernando. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética. Laboratorio de Insectos de Importancia Económica; Argentina. Fil: Segura, Diego Fernando. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Devescovi, Francisco. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética. Laboratorio de Insectos de Importancia Económica; Argentina. Fil: Devescovi, Francisco. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Muntaabski, Irina. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética. Laboratorio de Insectos de Importancia Económica; Argentina. Fil: Muntaabski, Irina. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina Fil: Milla, Fabian Horacio. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética. Laboratorio de Genética de Insectos de Importancia Económica; Argentina. Fil: Milla, Fabian Horacio. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina. Fil: Scannapieco, Alejandra Carla. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética. Laboratorio de Insectos de Importancia Económica; Argentina. Fil: Scannapieco, Alejandra Carla. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina. Fil: Cladera, Jorge Luis. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética. Laboratorio de Insectos de Importancia Agronómica; Argentina. Fil: Cladera, Jorge Luis. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina. Fil: Lanzavecchia, Silvia Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética. Laboratorio de Insectos de Importancia Económica; Argentina. Fil: Lanzavecchia, Silvia Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina.

Este artículo contiene 37 páginas, 16 figuras, 2 tablas., During a visit to polychaete–rearing facilities in the vicinity of Bay of Ca´diz (SW Iberian Peninsula, Atlantic Ocean), we sampled two populations of Marphysa (Annelida, Eunicidae) originally occurring at nearby intertidal soft bottoms, one being more than twice as long as the other at the same age. We analysed them using partial sequences of two mitochondrial genes, 16S rDNA and Cytochrome Oxidase I, and classical morphological observations. Our molecular results confirmed that the two populations corresponded to two different species, with PTP species delimitation values ranging from 0.973 (long–bodied species) to 0.999 (short–bodied species). Morphologically, the short–bodied species resembles the recently redescribed M. sanguinea (Montagu, 1813), but differs mainly in having some parapodia with two subacicular hooks (one bidentate and one unidentate) and three types of pectinate chaetae, Two isodont present all along the body, and one particularly large anodont asymmetric appearing only from mid–posterior parapodia. The long–bodied species resembles Marphysa aegypti Elgetany, El-Ghobashy, Ghoneim and Struck, 2018 both in size and in having very robust, unidentate subacicular hooks (single in most parapodia, two–both similar in size and form–in some posterior parapodia), but differs, among other features, in the maxillary formula, the number of acicula per parapodia and the number and shape of pectinate chaetae. Accordingly, we are here fully illustrating and formally describing the two Iberian populations as Marphysa gaditana sp. nov. (short–bodied) and Marphysa chirigota sp. nov. (long–bodied) and we are emending the description of M. aegypti based on our revision of the type material. Also, we discuss on the distribution of the species of the sanguinea– group and on the relevancy of taxonomically robust studies when dealing with species of commercial interest having the potential of being globally spread through human activities, as well as on the misunderstandings caused by the incorrect use of the “cosmopolitan species” concept., This study received funds from the Linnean Society of London and the Systematics Association through the 2915 Systematics Research Fund call. The project funded was entitled “Cryptic Fish Baits.” DM received funding from the Consolidated Research Group on Marine Benthic Ecology, Generalitat de Catalunya (http://agaur. gencat.cat), grant 2017SGR378 and the Agencia Estatal de Investigacio´n (AEI) (http://www.ciencia. gob.es/portal/site/MICINN/aei), EuropeanRegional Development Fund (FEDER) (https://ec.europa.eu/ regional_policy/en/funding/erdf/), grant CTM2017– 88080 / PopCOmics.

Insects possess highly developed olfactory systems which play pivotal roles in its ecological adaptations, host plant location, and oviposition behavior. Bactrocera minax is an oligophagous tephritid insect whose host selection, and oviposition behavior largely depend on the perception of chemical cues. However, there have been very few reports on molecular components related to the olfactory system of B. minax. Therefore, the transcriptome of B. minax were sequenced in this study, with 1 candidate chemosensory protein (CSP), 21 candidate odorant binding proteins (OBPs), 53 candidate odorant receptors (ORs), 29 candidate ionotropic receptors (IRs) and 4 candidate sensory neuron membrane proteins (SNMPs) being identified. After that, we sequenced the candidate olfactory genes and performed phylogenetic analysis. qRT-PCR was used to express and characterize 9 genes in olfactory and non-olfactory tissues. Compared with GFP-injected fly (control), dsOBP21-treated B. minax and dsCSP-treated B. minax had lower electrophysiological response to D-limonene (attractant), suggesting the potential involvement of BminOBP21 and BminCSP genes in olfactory perceptions of the fly. Our study establishes the molecular basis of olfaction, tributary for further functional analyses of chemosensory processes in B. minax.

Dipteran or “true” flies occupy nearly every terrestrial habitat, and have evolved to feed upon a wide variety of sources including fruit, pollen, decomposing animal matter, and even vertebrate blood. Here we analyze the molecular, genetic and cellular basis of odor response in the tsetse fly Glossina morsitans, which feeds on the blood of humans and their livestock, and is a vector of deadly trypanosomes. The G. morsitans antenna contains specialized subtypes of sensilla, some of which line a sensory pit not found in the fruit fly Drosophila. We characterize distinct patterns of G. morsitans Odor receptor (GmmOr) gene expression in the antenna. We devise a new version of the “empty neuron” heterologous expression system, and use it to functionally express several GmmOrs in a mutant olfactory receptor neuron (ORN) of Drosophila. GmmOr35 responds to 1-hexen-3-ol, an odorant found in human emanations, and also alpha-pinene, a compound produced by malarial parasites. Another receptor, GmmOr9, which is expressed in the sensory pit, responds to acetone, 2-butanone and 2-propanol. We confirm by electrophysiological recording that neurons of the sensory pit respond to these odorants. Acetone and 2-butanone are strong attractants long used in the field to trap tsetse. We find that 2-propanol is also an attractant for both G. morsitans and the related species G. fuscipes, a major vector of African sleeping sickness. The results identify 2-propanol as a candidate for an environmentally friendly and practical tsetse attractant. Taken together, this work characterizes the olfactory system of a highly distinct kind of fly, and it provides an approach to identifying new agents for controlling the fly and the devastating diseases that it carries., Author summary African trypanosomiasis, also known as “sleeping sickness” in humans and “wasting disease” in livestock, is a lethal and economically burdensome disease that afflicts rural communities throughout sub-Saharan Africa. The parasite that causes the disease is spread by the tsetse fly, which feeds on the blood of humans and their livestock. One effective strategy to control tsetse and the diseases that it carries has been to attract the fly into traps, or repel the fly, with odorants. The efficiency of this approach can be greatly improved through understanding of the molecular and cellular machinery of tsetse olfaction, and by identification of odorants that manipulate it. Here we provide findings on the anatomical, cellular, and molecular underpinnings of tsetse olfaction, which previously has been greatly understudied. We characterize the expression of odor receptors in the antenna and study their function with a new version of an in vivo expression system. We identify receptors that respond to ecologically relevant odors in the tsetse fly's environment. One receptor, which is expressed in an unusual pit structure, responds to odorants that attract tsetse and may mediate attraction. We identify an odorant that activates this receptor and that could be useful in combatting African trypanosomiasis.

A recent DNA-based assessment of the psyllid fauna of New Zealand recorded high genetic variation between populations that were expected to belong to the same psyllid species. Among these, a number of populations of the kōwhai psyllid Psylla apicalis (Ferris & Klyver, 1932), from a kōwhai species, Sophora microphylla Aiton (Fabaceae), presented high genetic variability. This gave new endorsement of an 87-year-old observation made by the entomologists Ferris and Klyver who, when describing the kōwhai psyllid, from Sophora tetraptera J.S. Muell., suggested that morphological variations could support more than one species. Accordingly, the morphological assessment conducted here, together with the genetic information now available, resulted in the description of Psylla frodobagginsi sp. nov. as a second New Zealand endemic psyllid species hosted by S. microphylla.

A putative male-produced pheromone has recently been described for the global pest of pines, Sirex noctilio, but field-activity has not been demonstrated. This study aimed to investigate the pheromone biology of S. noctilio in more detail. Specifically, we i) analysed effluvia and extracts for additional compounds by gas chromatography coupled with electro-antennographic detection (GC-EAD), mass spectrometry (GC-MS) and two dimensional time of flight mass spectrometry (GC X GC TOF MS), ii) conducted dose-response experiments for putative pheromone components, iii) determined the site of synthesis/ storage of the putative pheromone and iv) determined the release rate of the putative pheromone from males and three types of lures. A blend of four compounds was identified, including the previously described (Z)-3-decenol and (Z)-4-decenol, and two new compounds (Z)-3-octenol and (Z)-3-dodecenol. All compounds elicited a response from both male and female antennae, but the strength of the response varied according to sex, compound and dose tested. (Z)-3-Decenol and (Z)-3-octenol at lower and higher doses, respectively, elicited larger responses in males and females than the other two compounds. (Z)-3-Octenol and (Z)-4-decenol generally elicited larger female than male antennal responses. The site of synthesis and/or storage in males was determined to be the hind legs, likely in the leg-tendon gland. The relative release rate of the major compound by male wasps was shown to be 90 ± 12.4 ng/min, which is between 4 and 15 times greater than that observed from typical lures used previously. These observations are consistent with the hypothesis that these compounds may mediate lek formation in S. noctilio males and lek location in females.

We describe the immature stages ofMigonemyia migonei, which is the vector ofLeishmania (Viannia) braziliensis, the etiological agent of cutaneous leishmaniasis in South America, and a putative vector ofLeishmania infantum chagasi. Scanning Electron Microscopy (SEM) was used to refine the description of the structures of the egg, all instar larvae, and the pupa. The eggs have polygonal cells on the egg exochorion, and differences between larval and pupal chaetotaxy have been highlighted. Different sensillary subtypes—trichoidea, basiconica, coelonica and campanoformia—were observed in the larval stages. The results presented herein contribute to the taxonomy ofMg.migoneiand may contribute to future studies on the phylogeny of this important vector species.

Tsetse fly exhibit species-specific olfactory uniqueness potentially underpinned by differences in their chemosensory protein repertoire. We assessed 1) expansions of chemosensory protein orthologs in Glossina morsitans morsitans, Glossina pallidipes, Glossina austeni, Glossina palpalis gambiensis, Glossina fuscipes fuscipes and Glossina brevipalpis tsetse fly species using Café analysis (to identify species-specific expansions) and 2) differential expressions of the orthologs and associated proteins in male G. m. morsitans antennae and head tissues using RNA-Seq approaches (to establish associated functional molecular pathways). We established accelerated and significant (P90% of chemosensory transcripts) included cilium-associated mechanoreceptors, chemo-sensation, neuronal controlled growth/differentiation and regeneration/responses to stress. The expanded and tsetse fly species specific orthologs includes those associated with known tsetse fly responsive ligands (4-methyl phenol, 4-propyl phenol, acetic acid, butanol and carbon dioxide) and potential tsetse fly species-specific responsive ligands (2-oxopentanoic acid, phenylacetaldehyde, hydroxycinnamic acid, 2-heptanone, caffeine, geosmin, DEET and (cVA) pheromone). Some of the orthologs can potentially modulate several tsetse fly species-specific behavioral (male-male courtship, hunger/host seeking, cool avoidance, hygrosensory and feeding) phenotypes. The putative tsetse fly specific chemosensory gene orthologs and their respective ligands provide candidate gene targets and kairomones for respective downstream functional genomic and field evaluations that can effectively expand toolbox of species-specific tsetse fly attractants, repellents and other tsetse fly behavioral modulators., Author summary Tsetse flies are insect vectors of sleeping sickness in humans and nagana in livestock in sub-Sahara Africa. Tsetse flies identify their hosts (preferred and non-preferred) by detecting and processing odor cues emitted by the hosts in their environment. Tsetse flies use chemosensory proteins and associated pathways in their antennae to identify these cues. In this study, we identified expansions of these chemosensory protein in six tsetse fly species (Glossina morsitans morsitans, Glossina pallidipes, Glossina austeni, Glossina palpalis gambiensis, Glossina fuscipes fuscipes and Glossina brevipalpis) with different known hosts. We also identified potential ligands to these proteins based on fruit fly (Drosophila melanogaster) orthologs. With G. m. morsitans as an example, we identified the proteins and associated molecular pathways preferentially expressed in tsetse fly antennae. These proteins may be responsible for the tsetse fly species-specific host discrimination, with the ligands eliciting species-specific behavioral responses in the flies. The expressed orthologs may be functionally important in odor detection in tsetse fly and lay down useful groundwork for downstream functional genomics R&D for more effective tsetse fly species-specific odor attractants and repellents for routine tsetse fly control operations.

Insect courtship and mating depend on integration of olfactory, visual, and tactile cues. Compared to other insects, Bombyx mori, the domesticated silkworm, has relatively simple sexual behaviors as it cannot fly. Here by using CRISPR/Cas9 and electrophysiological techniques we found that courtship and mating behaviors are regulated in male silk moths by mutating genes in the sex determination cascade belonging to two conserved pathways. Loss of Bmdsx gene expression significantly reduced the peripheral perception of the major pheromone component bombykol by reducing expression of the product of the BmOR1 gene which completely blocked courtship in adult males. Interestingly, we found that mating behavior was regulated independently by another sexual differentiation gene, Bmfru. Loss of Bmfru completely blocked mating, but males displayed normal courtship behavior. Lack of Bmfru expression significantly reduced the perception of the minor pheromone component bombykal due to the down regulation of BmOR3 expression; further, functional analysis revealed that loss of the product of BmOR3 played a key role in terminating male mating behavior. Our results suggest that Bmdsx and Bmfru are at the base of the two primary pathways that regulate olfactory-based sexual behavior., Author summary The fundamental insect sexual behaviors, courtship and mating, result from successful integration of olfactory, vision, tactile and other complex innate behaviors. In the widely used insect model, Drosophila melanogaster, the sex determination cascade genes fruitless and doublesex are involved in the regulation of courtship and mating behaviors; however, little is known about the function of these sexual differentiation genes in regulating sex behaviors of Lepidoptera. Here we combine genetics and electrophysiology to investigate regulation pathway of sexual behaviors in the model lepidopteran insect, the domesticated silk moth, Bombyx mori. Our results support the presence of two genetic pathways in B. mori, named Bmdsx-BmOR1-bombykol and Bmfru-BmOR3-bombykal, which control distinct aspects of male sexual behavior that are modulated by olfaction. This is the first comprehensive report about the role of sex differentiation genes in the male sexual behavior in the silk moth.

Diaphorina citri Kuwayama is the most economically important citrus pest which is the primary vector of Candidatus Liberibacter spp. causing citrus greening (huanglongbing, HLB) disease. To better understand the developmental and structural changes of antennae and antennal sensilla in D. citri nymphs, we investigated the antennal morphology, structure and sensilla distribution of the five nymphal stages of D. citri using scanning electron microscopy. The antennae of the five different nymphal stages of D. citri were filiform in shape, which consisted of two segments in the first-, second- and third-instar nymphs; three segments in the fourth- and fifth-instar nymphs. The length of their antennae was significantly increased with the increase of the nymphal instar, as well as the total number of antennal sensilla. Ten morphological sensilla types were recorded altogether. They were the long terminal hair (TH1), short terminal hair (TH2), sensilla trichoidea (ST), cavity sensillum 1 (CvS1), cavity sensillum 2 (CvS2), sensilla basiconica 1-3 (SB1-3), sensilla campaniform (SCA) and partitioned sensory organ (PSO). Also, the distribution of antennal sensilla in each nymphal stage of D. citri was asymmetrical. The SBs only occurred on the antennae of the third-, fourth- and fifth-instar nymphs. Only one CvS2 was found in the third- and fifth-instar nymphs, and one SCA in the fourth- and fifth-instar nymphs, respectively. The possible roles of the nymphal antennal sensilla in D. citri were discussed. The results could contribute to a better understanding of the development of the sensory system, and facilitate future studies on the antennal functions in D. citri nymphs.

Cave animals provide a unique opportunity to study contrasts in phenotype and life history in strikingly different environments when compared to surface populations, potentially related to natural selection. As such, we compared a permanent cave-living Gammarus lacustris (L.) population with two lake-resident surface populations analyzing morphology (eye- and antennal characters) and life-history (size at maturity, fecundity and egg-size). A part of the cytochrome c oxidase subunit I gene in the mitochondrion (COI) was analyzed to contrast genetic relationship of populations and was compared to sequences in GenBank to assess phylogeography and colonization scenarios. In the cave, a longer life cycle was implied, while surface populations seemed to have a shorter life cycle. Egg size, and size at maturity for both sexes, were larger in the cave than in surface populations, while fecundity was lower in the cave than in surface populations. The cave population had longer first- and second antennae with more articles, longer first- and second peduncles, and fewer ommatidia than surface populations. The cold low-productive cave environment may facilitate different phenotypic and life-history traits than in the warmer and more productive surface lake environments. The trait divergences among cave and surface populations resembles other cave-surface organism comparisons and may support a hypothesis of selection on sensory traits. The cave and Lake Ulvenvann populations grouped together with a sequence from Slovenia (comprising one genetic cluster), while Lake Lille Lauarvann grouped with a sequence from Ukraine (comprising another cluster), which are already recognized phylogenetic clusters. One evolutionary scenario is that the cave and surface populations were colonized postglacially around 9 000–10 000 years ago. We evaluate that an alternative scenario is that the cave was colonized during an interstadial during the last glaciation or earlier during the warm period before onset of the last glaciation. publishedVersion

Three fruit borers Conogethes punctiferalis (Guenee) (Crambidae), Grapholita molesta Busck (Tortricidae), and Spilonota albicana Motschulsky (Tortricidae) are serious pests of fruit trees. In this study, their antennal morphology, types of sensilla, and distributions were observed by using SEM (Scanning Electron Microscope). Nine types of sensilla were found on the antennae of C. punctiferalis, while eight types of sensilla were presented on each of G. molesta and S. albicana. The sensilla trichodea with two subtypes were the most abundant sensilla among three fruit borers. Two subtypes of sensillum coeloconica (type I with spines and type II without spines) were observed on the antennae of C. punctiferalis and G. molesta. However, sensilla coeloconica (type I) were only found in S. albicana. Although the sensilla campaniformia were only found on the antennae of C. punctiferalis, our observations confirm sensilla campaniformia presence in the moths. In addition, the functions of these sensilla were discussed based on previously reported lepidopteran insects. As a result, our study may provide useful information for advanced electrophysiological and behavioral experiments to better understand the mechanisms related to pests control.

Among the many challenges in paleobiology is the inference and reconstruction of behaviors that rarely, if ever, leave a physical trace on the environment that is suitable for fossilization. Of particular significance are those behaviors tied to mating and courtship, individual interactions critical for species integrity and continuance, as well as those for dispersal, permitting the taxon to expand its distribution as well as access new habitats in the face of local or long-term environmental change. In this context, two recently discovered fossils from the Early Cretaceous amber of Spain (ca. 105 mya) give a detailed view of otherwise fleeting ethologies in Collembola. These occurrences are phylogenetically spaced across the class, and from species representing the two major clades of springtailsÐS ymphypleona and Entomobryomorpha. Specifically, we report unique evidence from a symphypleonan male (Pseudosminthurides stoechus Sánchez-García & Engel, 2016) with modified antennae that may have functioned as a clasping organ for securing females during mating on water's surface, and from an aggregation of entomobryomorphan individuals (Proisotoma communis Sánchez-García & Engel, 2016) purportedly representing a swarming episode on the forest floor. We demonstrate that the mating behavioral repertoire in P. stoechus, which is associated with considerable morphological adaptations, likely implied elaborate courtship and maneuvering for guarantee sperm transfer in an epineustic species. These discoveries reveal significant behaviors consistent with modern counterparts and a generalized stasis for some ancient hexapod ethologies associated with complex mating and courtship and social or pre-social aggregations, so critical to specific constancy and dispersal., Departament de Dinàmica de la Terra i de l'Oceà, Universitat de Barcelona, España, Institut de Recerca de la Biodiversitat, Universitat de Barcelona, España, Museo Geominero, Instituto Geológico y Minero de España, España, Division of Entomology, Natural History Museum, University of Kansas, Estados Unidos, Department of Ecology and Evolutionary Biology, University of Kansas, Estados Unidos, Division of Invertebrate Zoology, American Museum of Natural History, Estados Unidos

Despite the popular use of hummingbird feeders, there are limited studies evaluating the effects of congregation, sharing food resources and increased contact when hummingbirds visit feeders in urban landscapes. To evaluate behavioral interactions occurring at feeders, we tagged 230 individuals of two species, Anna's and Allen's Hummingbirds, with passive integrated transponder tags and recorded their visits with RFID transceivers at feeders. For detecting the presence of tagged birds, we developed an RFID equipped feeding station using a commercially available antenna and RFID transceiver. Data recorded included the number of feeder visits, time spent at the feeder, simultaneous feeder visitation by different individuals, and identifying which feeders were most commonly visited by tagged birds. For the study period (September 2016 to March 2018), 118,017 detections were recorded at seven feeding stations located at three California sites. The rate of tagged birds returning to RFID equipped feeders at least once was 61.3% (141/230 birds). Females stayed at feeders longer than males per visit. We identified primary, secondary and tertiary feeders at Sites 2 and 3, according to the frequency of visitation to them, with a mean percentage of 86.9% (SD±19.13) visits to a primary feeder for each tagged hummingbird. During spring and summer, hummingbirds visited feeders most often in morning and evening hours. Feeder visits by males overlapped in time with other males more frequently than other females. The analysis of the contact network at the feeders did not distinguish any significant differences between age or sex. Although most hummingbirds visited the feeders during the daytime, our system recorded night feeder visitations (n = 7 hummingbirds) at one site. This efficient use of RFID technology to characterize feeder visitations and contact networks of hummingbirds in urban habitats could be used in the future to elucidate behaviors, population dynamics and community structure of hummingbirds visiting feeders.

This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Global Positioning System (GPS) technology is widely used in wildlife research to study animal movement and habitat use. In order to evaluate the quality and reliability of GPS data, the factors influencing the performance of these devices must be known, especially for semiaquatic species, because terrestrial and aquatic habitat might affect GPS performance differently. We evaluated the location error and fix success rate of three GPS receiver models in stationary tests and on a semi-aquatic mammal, the Eurasian beaver (Castor fiber). The location error during stationary tests was on average 15.7 m, and increased with increasing canopy closure, slope, and horizontal dilution of precision, potentially leading to the erroneous classification of GPS positions when studying habitat use in animals. In addition, the position of the GPS antenna (flat versus 90˚ tilted) affected the location error, suggesting that animal behavior affects GPS performance. The fix success rate was significantly higher during stationary tests compared to when GPS units were deployed on beavers (94% versus 86%). Further, GPS receivers did not obtain any positions underwater and underground, the latter potentially allowing the estimation of activity periods in animals that use lodges or burrows as shelter. We discuss the possibilities for data screening, the use of buffer zones along the shoreline, and combination with other data loggers to avoid the erroneous classification of GPS positions when studying habitat use.

Cyrtorhinus lividipennis Reuter (Hemiptera: Miridae: Orthotylinae), including nymphs and adults, are one of the dominant predators and have a significant role in the biological control of leafhoppers and planthoppers in irrigated rice. In this study, we investigated the antennal morphology, structure and sensilla distribution of C. lividipennis in different instars using scanning electron microscopy. The antennae of both five different nymphal stages and adults were filiform in shape, which consisted of the scape, pedicel and flagellum with two flagellomeres. There were significant differences found in the types of antennal sensilla between nymphs and adults. The multiporous placodea sensilla (MPLA), basiconica sensilla II (BAS II), and sensory pits (SP) only occurred on the antennae of adult C. lividipennis of both sexes. Moreover, there was chaetica sensilla III (CHA III) only observed in males. Sixteen types of antennal sensilla were recorded altogether. They were microtrichia sensilla (MIC), three types of trichoidea sensilla (TRI I-III), three types of chaetica sensilla (CHA I-III), three types of basiconica sensilla (BAS I-III), two types of coeloconica sensilla (COE I and COE II), placodea sensilla (PLA), campaniform sensilla (CAM), MPLA, and SP. In the five different nymphal stages of C. lividipennis, the length of their antennae was significantly increased with the increase of the instar, as well as the number of the TRI II and TRI III. Moreover, sexual dimorphism usually occurred not only in the distribution (CHA III and SP) and the number of antennal sensilla (MIC, BAS II, TRI II, TRI III and MPLA), but also in the length of flagellum (F1 and F2). The possible functions of antennal sensilla are discussed. Those observations could contribute to a better understanding of the development of the olfactory system, and facilitate future studies on the antennal functions in C. lividipennis.

Antenna selection in Multiple-Input Multiple-Output (MIMO) systems has attracted increasing attention due to the challenge of keeping a balance between communication performance and computational complexity. Recently, deep learning based methods have achieved promising performance in many application fields. This paper proposed a deep learning (DL) based antenna selection technique. First, we generated the label of training antenna systems by maximizing the channel capacity. Then, we adopted the deep convolutional neural network (CNN) on the channel matrices to explicitly exploit the massive latent cues of attenuation coefficients. Finally, we used the adopted CNN to assign the class label and then select the optimal antenna subset. Experimental results demonstrate that our method can achieve better performance than the state-of-the-art baselines for data-driven based antenna selection.