Cytochemistry of fat body trophocytes and ovaries of workers and queens of Melipona quadrifasciata anthidioides (Hymenoptera: Apidae: Meliponini) during vitellogenesis

ABSTRACT The fat body (FB) of insects is where yolk proteins are synthesized. Therefore, relationships between the FB and oogenesis were studied in nurse workers, virgins, and physogastric queens of Melipona quadrifasciata anthidioides, a stingless bee in which the workers produce and lay eggs while provisioning brood cells. The relationships between FB and oogenesis, as well as the routes of materials from hemolymph to the oocytes, were studied through the cytochemical detection of lipids by osmium imidazole (OI), carbohydrates by ruthenium red (RR) and basic proteins by ammoniacal silver (AS). The results show differences in the presence of the studied materials in FB trophocytes and ovary of the classes of females studied and oogenesis phases. Material that tested positive for the treatments was detected among the classes of individuals studied in both, trophocytes and oocytes, and in the route of those materials from hemolymph to the oocytes. The differences found among the individual classes indicate relationships with the nutrition and adaptation to the parsimonious use of nutrients in the metabolism of reproduction. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.     

Asymmetrical distribution of antennal sensilla in the female Anastatus japonicus Ashmead (Hymenoptera: Eupelmidae)

Anastatus japonicus Ashmead (Hymenoptera: Eupelmidae) is an important egg parasitoid of several major insect pests. To better understand its host finding mechanisms, the antennal sensilla of female wasp were investigated by scanning electron microscopy. Sensilla chaetica were found mainly on radicle and pedicel segments of the antennae. i-Type sensilla, s. campaniformia, and corneous sensilla were detected on the leeward side, while s. coeloconica and lance sensilla were presented on the windward side of the antennae. S. trichodea and s. basiconica were more abundant on the leeward side than on the windward side of the antennae. More s. placodea were found on the windward side than on the leeward side of the right antenna, while the opposite results were observed on the left antenna. Overall, more s. placodea were found on the right antenna than that on the left antenna. The numbers of s. trichodea and s. basiconica on the clava or the third flagellum antennomere of the right antenna were more than those of the left antenna, whereas their distribution patterns on the other corresponding antennomeres were reverse. Our results showed that there is a strong asymmetrical antennal sensilla distribution quantitatively and spatially between the left and right antennae. Placoid sensilla are present more on the right antenna than on the left antenna. S. campaniformia, corneous sensilla, and i-type sensilla were found only on the leeward side of the antennal clava, while their external morphology and potential functions were described and discussed in detail for the first time.     

Sexual dimorphism in antennal morphology and sensilla ultrastructure of a pupal endoparasitoid Tetrastichus howardi (Olliff) (Hymenoptera: Eulophidae)

Tetrastichus howardi (Olliff) (Hymenoptera: Eulophidae), a pupal parasitoid of a great number of Lepidoptera pests, has a great potential for biological control. To investigate the olfactory system of this parasitoid, we examined the morphology and ultrastructure of the antennal sensilla of both male and female T. howardi using scanning and transmission electron microscopic techniques. Antennae of male and female T. howardi were geniculate in shape, which consisted of scape, pedicel and flagellum with 5 and 4 flagellomeres, respectively. The sexual differences were recorded in the types, structure, distribution and abundance of antennal sensilla of T. howardi. Fourteen morphologically distinct types of antennal sensilla were found on the female antennae, while seventeen on the male antennae. They were: multiporous plate sensilla (MPS1‐4), chaetica sensilla (CH1‐3), multiporous trichodea sensilla (MTS), aporous trichodea sensilla (ATS1‐5), multiporous grooved peg sensilla (MGPS), coeloconic sensilla (COS), campaniform sensilla (CAS), terminal finger‐like hairy sensilla (TFI), cuticular pore (CP), and ventral sensory plaque (VSP). MPS4, ATS (3‐5), and VSP only occurred on the male antennae, while MPS2 and MPS3 only on the female antennae. The MPSs, MTS, MGPS, TFI, and CP may function as olfactory sensilla involving in detecting odor stimuli whereas the ATSs, CHs, and CAS may serve as mechanoreceptors. COS were presumed to play a role as chemo‐, thermo‐ or hygro‐receptor. The results could facilitate future studies on the biology of olfaction in T. howardi. Microsc. Res. Tech. 79:374–384, 2016. © 2016 Wiley Periodicals, Inc.     

Morphology and distribution of antennal sensilla of two tortricid moths,Cydia pomonella and C. succedana (Lepidoptera)

Morphology of antennal sensilla and their distributions were investigated in male and female adults of two tortricid moths, Cydia pomonella and C. succedana using scanning electron microscopy. The antennae of both sexes of the two species were filiform, and the overall lengths of the antennae and the number of consisting segments were greater in males than in females. Six types of sensilla (s.) were identified from the antennae of both sexes in the two species: s. trichodea, s. basiconica, s. coeloconica, s. auricillica, s. chaetica, and s. styloconica, in varying numbers and distribution along the antennae. Among them, surface of four sensilla types (s. trichodea, s. basiconica, s. coeloconica, s. auricillica) were multiporous in the two species, indicating that the primary function of these sensilla is olfactory. The s. trichodea were the most numerous on the antennae in both sexes of the two species. Male C. pomonella has a greater number of s. trichodea than the female. The four sensilla types were further divided into different subtypes in the two species; s. trichodea into three subtypes, s. basiconica into two subtypes, s. coeloconica into two subtypes in C. pomonella and one subtype in C. succedana, and s. auricillica into two subtypes. Sexual dimorphism was observed in the subtypes of s. trichodea. The long subtype of s. trichodea occurs only on male antennae, whereas the short subtypes mainly on female antennae. These findings would be helpful for further studies on detailed chemo‐receptive functions of each subtype of the antennal sensilla.     

Ultrastructure and distribution of antennal sensilla of the chilli thrips Scirtothrips dorsalis hood (Thysanoptera: Thripidae)

The chilli thrips, Scirtothrips dorsalis Hood, is a serious pest of numerous important vegetable and ornamental crops. Various signals, especially phytochemical cues, determine the behavior of the phytophagous thrips at host selection. The sensory abilities of S. dorsalis are poorly understood although the antennae of adult are known to possess important sensory structures in orther insects. In this study, the morphology, distribution, and ultrastructure of the antennal sensilla of the S. dorsalis were examined by using scanning and transmission electron microscopy. Microscopy observations revealed that adult male and female S. dorsalis possess filiform antennae. Each antenna comprises a scape, a pedicel, and a flagellum composed of six segments without clear sexual dimorphism in the number and distribution of antennal sensilla. The scape and pedicel exhibit Böhm's bristles, sensilla chaetica, and sensilla campaniform. The external structures of these organs reveal their mechanosensory function. In the flagellum, the most represented sensilla are the multiporous sensilla basiconica, which can be divided into three types of single‐walled olfactory sensilla; three types of sensilla chaetica with mechanosensory and gustatory functions; sensilla coeloconica, which possess hollow cuticular spoke channels and represent double‐walled olfactory sensilla; sensilla capitula and sensilla cavity with thermo‐hygrosensory functions; and aporous sensilla trichodea with smooth cuticula and mechanosensory function. The putative function of described sensilla is discussed in ralation to host plant selection behavior of S. dorsalis.     

Morphology and ultrastructure of antennal sensilla of the parasitic wasp Baryscapus dioryctriae (Hymenoptera: Eulophidae)

Baryscapus dioryctriae is an endoparasitic wasp in the pupae of many Pyralidae pests, such as Dioryctria mendacella, Ostrinia furnacalis, and Chilo suppressalis. To provide requisite background for our ongoing research on the mechanisms of host location in B. dioryctriae, the morphology, abundance, distribution, and ultrastructure of the antennal sensilla were investigated using scanning and transmission electron microscopy. The geniculate antennae of B. dioryctriae are composed of scape, pedicel, and flagellum. Eight types of sensilla including Böhm sensilla, chaetica, trichodea, basiconic capitate peg, campaniformia, placodea, coeloconica, and sensilla styloconicum with a long hair were identified on both sexes. Sexual dimorphism exists in the antennae of B. dioryctriae. The number of flagellomere in males is over females, and the subtypes and abundance of sensilla are also different between the sexes. Additionally, the possible functions of distinct sensilla were discussed, which varies from olfaction, contact chemoreceptive, mechanoreception to hygro-/thermoreception, especially, the sensilla trichodea and placodea might be involved in olfactory perception in B. dioryctriae. These results provide an essential basis for further study on chemical communication between B. dioryctriae and their hosts, and contribute to the development of B. dioryctriae becoming an effective biocontrol agent against the pests of agriculture and forestry.     

Morphology and distribution of antennal sensilla in egg parasitoid,Ooencyrtus nezarae (Hymenoptera: Encyrtidae)

Morphology of antennal sensilla and their distribution were investigated in adults of Ooencyrtus nezarae, an egg parasitoid of Riptortus pedestris, using scanning electron microscopy. Male antennae was found to be significantly greater in overall length than female antennae. The antenna of O. nezarae was composed of the radicula, scape, pedicel, funicle and clava in both sexes, with seven types of sensilla identified: sensillum trichodea; s. finger‐like; s. placoidea; s. chaetica; s. basiconica; s. coeloconica, and s. campaniform. They occur in varying number and distribution along the antennae. Two sensillum types were further categorized into additional subtypes, with two subtypes in s. trichodea and three in s. chaetica. Among all characterized sensilla, s. trichodea subtype 1 and s. placoidea were multiporous, indicating that the primary function of these sensilla is olfactory. Sensillum trichodea was the most abundant sensillum type on the antennae of both sexes. Sexual dimorphism was only observed from the subtype 1 sensilla of s. trichodea in males and the subtype 3 sensilla of s. chaetica in females. The morphological information established in our study may provide useful information for further investigations in sensory physiological function of each morphological type of sensilla and their related behavior in this egg parasitoid.     

Scanning electron microscopy studies of antennal sensilla of Ooencyrtus phongi (Hymenoptera: Encyrtidae)

Ooencyrtus phongi (Hymenoptera: Encyrtidae) is an important egg parasitoid of the litchi stink bug, Tessaratoma papillosa (Drury) (Hemiptera: Tessaratomidae). Antennae of parasitic Hymenoptera are important sensory organs and play an important role in host location, host discrimination, courtship, and mating behavior. In this article, we examined the external morphology of the antennal sensilla of female and male of O. phongi using scanning electron microscopy. Twelve morphological sensillar types were recognized in both sexes, including the placoid sensilla, basiconic sensilla, two types of sensilla trichodea, and eight types of sensilla chaetica. Major differences were found between the sexes, in number, distribution, shape, structure, and size of the identified sensilla. These results are discussed in relation to the possible role of these sensilla in the host location behavior of O. phongi.     

Ultrastructure of antennal sensilla of Erannis ankeraria Staudinger (Lepidoptera: Geometridae)

Erannis ankeraria Staudinger, 1861 (Lepidoptera: Geometridae) is one of the major pests causing serious damages on Larix spp., Quercus L., and Picea Mill. To investigate the conceivable functions of antennal sensilla associated with pheromone detection, we observed the ultrastructure of antennae in female and male of E. ankeraria moths by scanning electron microscopy. Six types (including two subtypes and a new type) of sensilla were recorded and characterized, including Sensilla trichodea (ST I and ST II), Böhm bristles, Sensilla squamiformia, Sensilla chaetica, Sensilla auricillic (SAU) and newly observed serrate‐like sensilla. ST I and SAU were abundant on male antennae, displaying a sexual dismorphism. Serrate‐like sensilla were also peculiar to male antennae. In summary of reported functions of corresponding sensilla, we presumed putative functions of the recorded sensilla in E. ankeraria, providing the morphological basis for sensory mechanisms related to pest management.     

Effects of treatment of the fat body trophocytes of Melipona quadrifasciata anthidioides nurse workers and virgin queens in culture by juvenile hormone III and ecdysterone (20‐HE)

The fat body (FB) consists of two types of cells: throphocytes and oenocytes. Throphocytes are related to intermediary metabolism storing lipids, carbohydrates, and proteins while oenocytes play role in the lipids and lipoproteins production. The vitellogenin is the precursor of egg yolk (vitelline) and is synthesized on FB. The aim of this work was to analyze the effects of hormones acting in bee reproduction, as juvenile hormone (JH) and ecdisteroids (20 HE) on FB cells, where vitellogenin is synthesized. For the study were chose nurse workers that in Melipona quadrifasciata anthidioides present activated ovaries and produce eggs, and virgin queens whose ovaries are not yet activated, presenting only previtellogenic follicles. FB trophocytes from these classes of bees were cultivated in media containing different amounts of JH and 20‐HE. The effects on trophocytes cytoplasm reserves of lipids, proteins, and activity of acid phosphatase were compared by observing preparations from cultured FB, treated and control, by transmission electron microscopy (TEM). The results showed that the hormones effects are related to the bee's caste and functional ovary stage. The role of acid phosphatase on mobilization of the trophocyte reserves was also determined. Microsc. Res. Tech. 2013. © 2012 Wiley Periodicals, Inc.     

Types and numbers of sensilla on antennae and maxillary palps of small and large houseflies, Musca domestica (Diptera, Muscidae)

Houseflies, Musca domestica, obtained from a high-larval-density culture were significantly (ca. 1.5 times) smaller than those from a low-larval-density culture. The same held true for their antennae and maxillary palps. Structure, number, and distribution of sensilla on antennae and palps of small and large flies were investigated using Scanning electron microscopy and Transmission electron microscopy. In each funiculus three pits were present, two (Type I) consisting of several compartments and one (Type II) of one compartment. Four types of olfactory sensilla were detected: trichoid sensilla on the funiculi, basiconic sensilla on funiculi and palps, grooved sensilla on funiculi and in pits Type I, and clavate sensilla on funiculi and in pits Type II. Type I pits also contained striated sensilla (presumably hygroreceptors). Mechanosensory bristles were present on scapes, pedicels, and palps. Noninnervated microtrichia were found on the palps and all antennal segments. The large houseflies possessed nearly twice as much sensilla as the small flies. So far, we did not observe differences in behavior between small and large flies. We assumed that small flies, being olfactory less equipped than large flies, may be able to compensate for this by, e.g., visual cues or by their olfactory sensilla being more sensitive than those of large flies. To be able to answer these questions careful studies have to be done on the behavioral responses of small and large flies to environmental stimuli. In addition, electrophysiological studies should be performed to reveal whether the responses of individual sensilla of flies reared under different conditions have been changed.     

Antennal fine morphology of the threatened beetle Osmoderma eremita (Coleoptera: Scarabaeidae), revealed by scanning electron microscopy

The aim of this study was to characterize the antennal morphology of Osmoderma eremita, a threatened scarab beetle inhabiting tree hollows. O. eremita males produce a sex pheromone, (R)‐(+)‐γ‐decalactone, responsible mainly for the attraction of females but also other males. Gross and fine morphology of microstructures including sensilla, microsculpture and pores were analyzed using Scanning Electron Microscopy. The antenna of O. eremita showed the typical lamellicorn shape of scarab beetles, with a basal scape, a pedicel, a funicle composed of five antennomeres and a club composed of three lamellae. Six different subtypes of sensilla chaetica (Ch.1 ? 6), Böhm sensilla (Bo), one subtype of sensilla basiconica (Ba.1), two subtypes of sensilla coeloconica (Co.1 ? 2), two subtypes of sensilla placodea (Pl.1 ? 2), pores and peculiar folds were described. The two sexes did not show any significant differences in the occurrence and number of the sensilla placodea, known to be responsible for the pheromone reception. Instead, some sexual differences were found on the occurrence and topology of three different microstructures: (1) one subtype of sensillum chaeticum (Ch.2) occurring on the pedicel only in males; (2) a characteristic pore occurring on the funicle only in males; (3) a peculiar fold occurring on different antennomeres of the funicle in the two sexes, on the fourth in males and on the fifth in females. A comparison between sensilla of O. eremita and those of other Scarabaeoidea is provided. Microsc. Res. Tech. 79:178–191, 2016. © 2016 Wiley Periodicals, Inc.     

Ultrastructural observations on antennal sensilla of Cnaphalocrocis medinalis (Lepidoptera: Pyralidae)

The morphology and ultrastructure of the antennal sensilla of Cnaphalocrocis medinalis (Lepidoptera: Pyralidae) was studied by scanning and transmission electron microscopic techniques. Eight morphological types of sensillum were recorded in both sexes: sensilla trichodea (S. trichodea), sensilla basiconc (S. basiconc), sensilla coeloconica (S. coeloconica), sensilla styloconica (S. styloconica), sensilla squamous (S. squamous), sensilla auricillica (S. auricillica), B?hm bristles (B. bristles), and sensilla cavity (S. cavity). S. trichodea were the most abundant sensilla and were distributed over the entire antennal surface. Four different types of S. trichodea and S. basiconc were observed. The number of S. basiconc and S. coeloconica of males were greater than those of females of C. medinalis. S. squamous formed on the dorsal part of the antenna, as a cluster in females and as in a line in males. Higher magnification revealed that S. basiconc had an olfactory function, while the character of longer length of these sensilla suggested that they also played a rolein sensing mechanical or other chemical stimuli. Transmission electron microscopy (TEM) of S. squamous revealed nonporous walls suggesting a non-olfactory function. S. coeloconica, S. styloconica, and S. cavity may be involved in the perception of humidity, temperature, heat, and CO?. Because of their particular location, we infer that B. bristles may function in sensing the position and movements of the antennae, while the function of S. auricillica is as yet unknown. The results obtained provide direct morphological evidence that antennae possess structures that can play a role in finding mates and locating host plants.     

Observation of antennal sensilla in Xylotrechus grayii (Coleoptera: Cerambycidae) with scanning electron microscopy

The longicorn beetle Xylotrechus grayii (White, 1855) has been spreading rapidly in China, causing mass mortality of honeysuckle which is economically and medicinally important. In order to elucidate the mechanisms of mate and host location and to advance efficient control methods, antennal sensilla features were investigated in both sexes of X. grayii using scanning electron microscopy (SEM). The filiform antennae of both sexes consist of scape, pedicel, and nine flagellomeres (f1–9). Five types of sensilla were observed: sensilla chaetica (5 subtypes, SC1–5), sensilla basiconica (4 subtypes, SB1–4), Böhm bristles (Bm), grooved peg sensilla (Gp), and sensilla campaniformia (Ca). SC were most common on the antennae, followed by SB and Bm. No significant sexual differences in the type, amounts, and distribution of antennal sensilla were found except for the distribution of SB clusters and Ca. SB clusters and Ca occurred on f1–8 of male antennae but were absent on those segments in females, suggesting a potential function as receptors for female sex pheromones. The putative functions of other sensilla are discussed based on their characteristics in related species. This study provides an important foundation for further research on sensory mechanisms and control measures of X. grayii. Microsc. Res. Tech. 77:264–273, 2014. © 2014 Wiley Periodicals, Inc.     

Antennal sensilla and ovipositor morphology of the European birch sawfly Arge pullata Zadd (Hymenoptera: Tenthredinidae,Argidae)

Arge pullata Zadd is an important phytophagous pest that damages red birch Betula albo‐sinensis in Hubei Province, South China. Massive ecological and economic losses have been caused by this species, which threatens the ecological security of the Shennongjia Nature Reserve. To investigate the mechanoreception, chemoreception, and oviposition processes of A. pullata, scanning electron microscopy and optical confocal microscopy were used to reveal the typology, morphology, and distribution of ovipositor and antennal sensilla. The results show that A. pullata has clavate antennae and eight types of sensilla in total, including sensilla chaetica, sensilla trichodea (types 1–3), sensilla basiconica, sensilla coeloconica (types 1 and 2), and Böhm's bristles. Sensilla trichodea type 1 distributed only on male antennae; the densities of sensilla trichodea type 2 and sensilla basiconica differed between the sexes. The binding pattern of ovipositor valvulae was discovered, and one type of sensilla chaetica, two types of sensory pits, and tooth‐like cones as well as two types of microtrichia were found in the ovipositor. Based on morphological evidence and research on Hymenoptera, putative functions are suggested to increase our understanding of the mechanisms by which this species finds hosts and mates, and how oviposition takes place. Microsc. Res. Tech. 77:401–409, 2014. © 2014 Wiley Periodicals, Inc.     

Morphology and distribution of antennal sensilla in a parasitoid fly,Gymnosoma rotundatum (Diptera: Tachinidae)

Morphology of antennal sensilla and their distribution were investigated in male and female adults of the parasitoid fly Gymnosoma rotundatum (Diptera: Tachinidae) using scanning electron microscopy (SEM). The overall length and shape were not different between males and females from each other. Three basic types of sensilla (sensilla basiconica, s. chaetica, and s. coeloconica) were identified from both sexes, but with variations in numbers and distribution along the antennae. The s. basiconica and s. chaetica could be divided further into subtypes; s. basiconica into three subtypes and s. chaetica into two subtypes. All the basiconica subtypes 1, 2, and 3 were multiporous, indicating that their primary function was olfactory. The sensilla basiconica was most abundant on the antennae of both sexes. The abundance of s. basiconica subtype 1 was different, but other subtypes 2 and 3 were similar between males and females. There was no pore on the cuticular surface of the s. chaetica and s. coeloconica, suggesting that they are likely to be a mechanosensory or a thermohygroreceptory function. The abundance of the two sensillum types was similar between males and females. The morphological information obtained in our study provides a basis for future investigations into the sensory physiological function, and associated behaviors, of each type of sensilla in this parasitoid fly.     

Morphology and distribution of antennal sensilla of female Phyllotreta striolata (Fabricius) (Coleoptera: Chrysomelidae)

Phyllotreta striolata (Fabricius) is an important pest of Brassicaceae in Southeast Asia and North America. Using scanning electron microscopy, we observed the external structure, number, and distribution of the antennal sensilla in P. striolata females to discuss the putative function of these sensilla in host location and oviposition behaviors. The antenna of female P. striolata is filiform, composed of a scape, a pedicel, and a flagellum with 9 flagellomeres. Five types of sensilla were identified, including sensilla cheaetica, sensilla trichodea, Böhm bristles, sensilla auricillica, and sensilla basiconica (five subtypes, SB1–SB2). External structure and distribution of antennal sensilla are compared with data from other insect species. In addition, we discuss the possible functions of antennal sensilla based on their characteristics. Microsc. Res. Tech. 79:219–226, 2016. © 2016 Wiley Periodicals, Inc.     

Distribution and ultrastructure of the antennal sensilla of the grape weevil Naupactus xanthographus (Coleoptera: Curculionidae)

The grape weevil, Naupactus xanthographus Germar (Coleoptera: Curculionidae), is a polyphagous insect native to southern South America that causes considerable damage in grape and other fruit species. In this study, the morphology and ultrastructure of the antennae and the antennal sensilla of N. xanthographus were investigated using scanning electron microscopy and transmission electron microscopy. The antennae consist of a scape, a pedicel, a funicle, and a zone called the “club,” which are all formed by a total of 12 antennomers. Different types of sensilla were observed: sensilla trichoidea, sensilla chaetica type 1 and 2, sensilla basiconica, and sensilla rod‐like. No sexual dimorphism was observed. The possible functions of the sensilla are discussed in relation to their morphology and ultrastructure.     

Antennal sensilla of the pine weevil Pissodes nitidus Roel. (Coleoptera: Curculionidae)

The antennal sensilla of the pine weevil (Pissodes nitidus Roel.) were observed with scanning electron microscopy and transmission electron microscopy (TEM). The weevil antenna consists of a long scape, a pedicel, and a flagellum with 10 segments; the last four flagellum segments are fused, forming the antennal club, which is densely covered by various sensilla. In both sexes, six types of sensilla, sensilla palmate 1‐4, sensilla chaetica, sensilla trichoid, sensilla basiconic 1‐2, sensilla rod‐like 1‐3, sensilla falciform, were identified. Sensilla palmate represent a unique sensillum type in the Pissodes genus, and named here after their palmate shape, also represent the most abundant sensillum type. The TEM analysis of sensilla palmate represents the first such analysis of this sensillum type, and we speculate that the sensilla have an olfactory function. The sensilla trichoid and chaetica were evenly distributed on the three or four hair bands of the club, with much lower numbers than the palmate sensilla. No significant sexual differences in the types, numbers, and distribution of the antennal sensilla were found except for the size. TEM observation indicated that sensilla chaetica and trichoid may function as olfactory sensors. The putative functions of other sensilla type were also discussed with reference to their morphology, distribution, and ultrastructure. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc.     

Morphology and distribution of antennal sensilla in adults of Xylotrechus quadripes

Xylotrechus quadripes (Chevrolat) is the serious woodborer pest of arabica coffee (Coffea arabica L.). To further elucidate the behavior mechanism of the insect based on chemical odorant and to advance effective trapping methods, the typology, distribution, and abundance of antennal sensilla were investigated meticulously in both sexes of X. quadripes by scanning electron microscopy. The filiform antennae of both sexes are composed of 11 segments, namely the scape, pedicel, and nine flagellomeres (f1–9). Ten types (14 subtypes) of sensilla were identified morphologically: sensilla chaetica (three subtypes, Ch.1–3), sensilla basiconica (three subtypes, Ba.1–3), Böhm bristles (Bb), sensilla dentiform (De), sensilla trichodea (Tr), sensilla auricillica (Au), sensilla campaniformia (Ca), grooved peg sensilla (Gp), cuticular pores (Cp), and a newly observed sensillum, named sensilla cone (Cone). The sensilla were mainly distributed in flagellomeres, and the types and amounts increased in frequency from scape to the ninth flagellomere. The numbers of sensilla were the highest on the antennal dorsal side, while the lowest on the ventral side. The types of sensilla were the most abundant on the lateral side, and two sensilla basiconica (Ba.1–2) were found exclusively. The average number of Tr, Ba, and Au on the antenna of the males was significantly greater than females, while the Gp and Cp on the antenna of the females were significantly greater than males. Ca was exclusively occurred on the male antennae but was absent in females. This study discusses the putative functions of the antennal sensilla in adults of X. quadripes based on their characteristics in related species' sensilla, and these results provide an important foundation to clarify the ecological adaption, olfactory recognition mechanism, and to develop the chemical ecology control of X. quadripes.