Types Of Trichodea Research Articles

Sensilla on antennae and mouthparts of adult spruce bark beetle Ips typographus (Coleoptera: Curculionidae).

The spruce bark beetle, Ips typographus, is an invasive forest pest that occurs across Eurasia. To further understand the mechanism of insect-host chemical communication and the feeding choices of adult I. typographus, we examined the sensilla on the antennae and mouthparts of I. typographus using scanning electron microscopy. No sexual dimorphism in sensilla type or distribution was observed. Ten subtypes of antennal sensilla were identified: sensilla trichodea Types I-III (TR1 , TR2 , and TR3 ); sensilla chaetica Types I and II (CH1 and CH2 ); sensilla basiconica Types I-III (BA1 , BA2 , and BA3 ); sensilla coeloconica (CO); and Böhm sensilla (BS). BA2 were the most abundant among the antennal sensilla in both sexes. Thirteen mouthpart sensilla subtypes were observed: sensilla trichodea Types I-IV (TR1 , TR2 , TR3 , and TR4 ); sensilla chaetica Types I-III (CH1 , CH2 , and CH3 ); sensilla digitiformia (DI); sensilla basiconica Types I-II (BA1 and BA2 ); and sensilla styloconica Types I-III (ST1 , ST2 , and ST3 ). Among these, TR4 were the most abundant in both sexes. The apex of each maxillary and labial palp carried the same sensilla (BA2 , ST1 , ST2 , and ST3 ), although the apex of the maxillary palp contained more total sensilla. The functional roles of each sensilla type are discussed based on their external structure and distribution. The results provide a theoretical basis for further studies on the olfactory and feeding behaviors and electrophysiology of adult I. typographus.

Antennal morphology and localization of a general odorant-binding protein in the great wax moth, Galleria mellonella (Lepidoptera: Pyralidae)

The great wax moth, Galleria mellonella (L.), is a globally distributed pest for bee hives and, therefore, of significant importance for apiculture. In this study, the antennal morphology of G. mellonella was elucidated by light microscopy (LM) and scanning electron microscopy (SEM). Moreover, the putative function of the sensilla was studied by in situ hybridization of an odorant-binding protein (OBP)-encoding gene. Thus, an OBP subclass called general odorant-binding protein (GOBP) was used. Currently, GOBPs are related to the transport of sex pheromone and general volatiles in the sensilla of insects. Results indicate sexual dimorphism, with longer antennae for females than males. Sensilla morphology was similar to that reported in other moths, especially pyralids, with a total of seven types of sensilla, namely chaetica (SCH), trichodea (STR), coeloconica (SCO), styloconica (STY), auricilica (SAU), basiconica (SBA) and squamiformia (SSQ). Böhm’s bristles (BB) were also found. As expected due to the inverse sexual communication of G. mellonella, a higher abundance of pheromone-related STR subtype I, were determined in female compared to male antennae. More interestingly, we report the presence of a GOBP-encoding gene, found mainly in female STR and SCH. Therefore, the cross information between reported sensilla function and that of OBPs provides evidence to support not only the olfactory function of STR and SCH, but also the uncommon sexual communication that G. mellonella has developed.

Sensory Receptors Associated with the Labial Tip and Precibarium of Philaenus spumarius L. (Hemiptera: Aphrophoride).

The meadow spittlebug, Philaenus spumarius (Linnaeus) (Hemiptera: Aphrophoridae), is an important vector for the xylem-limited bacterium Xylella fastidiosa (Wells, Raju, Hung, Weisburg, Mandelco-Paul, and Brenner), which is associated with olive quick decline syndrome in southern Italy. The mouthparts of Hemiptera have important roles in host plant selection, feeding behavior and for vectoring pathogens that cause plant diseases. In this study, the functional morphology of the sensory structures located on the labium tip and precibarium of P. spumarius was investigated using scanning and transmission electron microscopy. The labium tip is composed of two symmetrical sensory complexes, each with five different types of sensilla: aporous sensilla trichodea type 1 and 2; uniporous sensilla chaetica type 1 and 2; and multiporous sensilla basiconica. The precibarium of P. spumarius has two kinds of sensory structures: bulbous sensilla and papillae sensilla. In particular, two groups of sensilla are located on the epipharynx: a distal group that consists of ten papillae sensilla and a proximal group composed of six papillae sensilla and two bulbous sensilla, while the hypopharynx has only two papillae sensilla. The involvement of these sensory structures in the context of feeding behavior and pathogen transmission is discussed.

Sexual dimorphism in antennal sensilla of Parthenium beetle <i>Zygogramma</i> <i>bicolorata</i>

In the present study, scanning electron microscopy was used to investigate the ultrastructure of sensilla present on the antennae of male and female Zygogramma bicolorata. The antennae in this insect consist of the scape, pedicel, and nine flagellomeres. Six types of sensilla were identified: sensilla trichodea type 1 and 2 (ST1, ST2), sensilla cavitae (SCa), sensilla chaetica (SCh), and sensilla basiconica type 1 and 2 (SB1, SB2). Sensilla were characterized on the basis of their size and density to find out whether sexual dimorphism exists in this species or not. We observed that the size of the antennomeres was comparatively larger in males than females. Moreover, sensilla chaetica were found on all antennomers and have the qualification of being the longest type, suggesting that they probably have a role in mechanoreception. There was an abundance of sensilla trichodea in both males and females, indicating its function as a chemoreceptor. Sensilla basiconica are believed to sense sex pheromones and hence their abundance was more in males as compared to females.

Sensilla on six olfactory organs of male Eogystia hippophaecolus (Lepidoptera: Cossidae).

Eogystia hippophaecolus (Hua et al.) is an important boring pest that primarily damages sea buckthorn, causing large ecological and economic damages in China. In this study, we used scanning electron microscopy to investigate the sensilla on six olfactory tissues of male E. hippophaecolus: antennae, labial palps, external genitals, propodeum, mesopodium, and metapedes. On the antennae, two types of sensillum trichodea, two types of sensillum basiconica, a type of sensillum coeloconica, and Böhm's bristles were found. The labial palps had sensilla trichodea and chaetica. On the external genitals, three types of sensilla trichodea were the only sensilla. Böhm bristles were found on the base of the tibia and at the terminus of the tarsus. Most sensilla were distributed on the tarsus of the three pairs of legs, and notably, a majority of which were sensilla trichodea and sensilla chaetica, were on the pretarsus and telotarsus of the three pairs of legs. In this study, the distribution, number, type, and morphology of the sensilla on six olfactory organs of E. hippophaecolus were determined, which established the foundation for a future immunohistochemical search of olfactory proteins. RESEARCH HIGHLIGHTS: Eogystia hippophaecolus is a serious pest of seabuckthorn. The distribution, number, type, and morphology of olfactory sensilla of E. hippophaecolus are determined. The function and distribution of sensilla are compared with those of other insects.

Morphology of antennae ofDendroctonus vitei(Coleoptera: Curculionidae: Scolytinae), with special reference to sensilla clustered into pit craters

AbstractAs reported recently by the authors, the third and fourth antennomeres of the antennal club of the bark beetleDendroctonus viteiWood (Coleoptera: Curculionidae: Scolytinae) possess conoid sensilla clustered inside spherical or bulb-shaped invaginations of the cuticle that resemble geological pit craters. These structures are novel relative to otherDendroctonusErichson species examined. The morphology and ultrastructure of different sensilla types on the antennal club and within the pit craters ofD. viteiare herein described in detail with the aid of light, environmental scanning electron, and transmission electron microscopy. Five types of sensilla were found: fluted, basiconica type I, and trichodea types I, II, and III. The pit craters were composed of clusters of multiporous sensilla basiconica arising from the inner surface of the concavities, and the morphology and ultrasructure of these sensilla are consistent with an olfactory function. The presence of pit craters in theD. viteion the anterior side of the antennal club is an diagnostic character for this species and an autapomorphy of great taxonomic importance within theDendroctonus frontalisZimmermann species complex.

External Morphology of Antennae and Mouthpart Sensillae of the Granary Weevil (Coleoptera: Curculionidae)

Abstract The ultrastructure of the antennal and mouthpart sensillae for the granary weevil, Sitophilus granarius L. (Coleoptera: Curculionidae), adult was examined with scanning electron microscopy. The cephalic capsule bears two types of sensillae—a multibranched sensillum and a multiporous peg sensillum. The multibranched sensillum was a structure not previously reported for the granary weevil or any other insect species, and is distinguished by its torpedo-shaped appearance. The multiporous peg sensillae, formed from multiple straight tubules, are distributed on the distal one-third of the rostrum. The mouthparts bear two types of sensillae—the multiporous peg sensillae on the labrum and mandibles, and short basiconic sensillae on the labial palps. The antenna consists of eight segments arranged on the scape, pedicel, and flagellum. Each antennal segment bears sqaumiform sensillae, and five types of sensillae were identified on the club segment. These sensillae are a trichodea Type I, trichodea Type I...

Sexual difference in antennal sensilla abundance, density and size in Callosobruchus rhodesianus (Coleoptera: Chrysomelidae: Bruchinae)

Sexual difference in antennal sensilla size and per area density has rarely been studied in insects. The bruchine seed beetle Callosobruchus rhodesianus (Pic) (Coleoptera: Chrysomelidae: Bruchinae) is distributed over Central and Southern Africa and is a pest of stored legume seeds, especially cowpeas Vigna unguiculata. Here, we study the type, abundance, morphology and per area density of antennal sensilla on each antennal segment and their sexual differences in C. rhodesianus. The antennae of normal individuals consist of the scape, pedicel and nine flagellomeres as in other congeneric species. Sizes of most antennomeres are larger in males than in females. We observed the following eight different types of antennal sensilla: sensilla trichodea types 1 and 2 (ST1, ST2), sensilla cavitae (SCa), sensilla chaetica (SC), sensilla basiconica types 1, 2 and 3 (SB1, SB2, SB3) and Bohm bristles (BB). The SCa is found on all antennomeres unlike in congeners (C. chinensis and C. maculatus). The ST1, the most numerous and longest antennal sensilla type, is denser and thinner in females than in males but more abundant in males than in females. Since the ST1 is considered to serve as a chemoreceptor, the sexual difference in the ST1 may benefit males in searching for mates.

Olfactory stimulation of Apis cerana indica towards different doses of volatile constituents: SEM and EAG approaches

Morphological and peripheral olfactory responses of antennal chemosensilla of Apis cerana indica, worker honeybee, to commonly occurring plant volatiles were recorded using SEM and EAG techniques, respectively. The antennae of A. cerana indica reveal the predominance of olfactory sensilla besides gustatory and mechanoreceptor cells. Ten different types of olfactory sensilla including sensilla basiconica, placodea type A and B, chaetica, coeloconica, coelocapitula, trichodea type A, B, C and D were reported. Of these, trichodea B and placodea A types were reported to be maximum. Responses to 47 commonly occurring plant volatiles (including 10 aromatic, 12 aliphatic, 04 green leaf volatile, 10 hydrocarbon monoterpene, 08 oxygenated monoterpenes and 03 sesquiterpenes compounds) were shown to elicit the response. Normalized EAG response, relative to the standard 1-hexanol, reveal significant differences between the chemicals and were concentration dependent. At 0.1mg/mL dose, the largest amplitude was obtained with p-cymene (119.74±6.94) followed by cinnamaldehyde (97.07±4.94) and veratrol (92.99±7.82). Furthermore, at 1.0mg/mL, maximum stimulation was reported with cinnamaldehyde (92.02±4.26) followed by phenethyl alcohol (86.02±2.63), benzyl alcohol (70.53±2.47), 2-heptanone (67.71±5.02) and 1-heptanol (67.56±2.8). Again, amplitude of the response was found to be maximum with cinnamaldehyde (115.59±6.73) followed by 1-heptanol (105.69±2.45) and citral (100.78±4.93) at 5.0mg/mL, whereas, at 10.0mg/mL, phenethyl alcohol (93.45±1.87) and 2-heptanone (93.14±1.85) showed highest stimulation followed by 2-pentanone (92.22±0.43). These documentations provide valuable information regarding how diversity in chemoreceptive antennal sensilla reveals better ability to sense a diversity of odors that are important cues to help honeybee distinguish among species of various flowering plants.

Effects of the Antennal Sensilla Distribution Pattern on the Behavioral Responses ofTribolium castaneum(Coleoptera: Tenebrionidae)

The morphology and distribution of sensilla on the antennal flagella of male and female adults of Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), were investigated by using scanning and transmission electron microscopy (SEM and TEM). Behavioral responses of male and female adults were measured with 12 host-plant and leaf-volatile stimuli. No sexual dimorphism was observed in the distribution and types of sensilla. Two types of sensilla, trichodea and basiconica, were observed on the antennae. Sensilla trichodea were distributed on all antennal segments but were most abundant on the last 3 segments. In contrast, sensilla basiconica were found exclusively on the last 3 segments of the antenna. TEM cross sections showed sensilla trichodea to have a thick cuticular wall and regular point-shaped pores around the cuticular wall. Sensilla basiconica possessed a thin wall and continuous pores and dendrites. The pores on the walls of the sensilla indicate that they play a role in sensing chemical stimuli and in olfactory functions. Female and male adults of T. castaneum showed broad overlap in their behavioral responses to various odors. Preference for some volatiles was noted, but after removal of the 3 terminal antennal segments, there was no significant preference for any compound that had been previously attractive to the beetles when tested with the complete antennae.

Electron microscope study on workers antennae and sting lancets of three subspecies of honey bee Apis mellifera L. (Hymenoptera: Apidae) and its bearing on their phylogeny

Ultrastructure of antennae and sting of the honey bee workers in three subspecies of Apis mellifera; Egyptian A. m. lamarckii, Carniolan A. m. carnica and Italian A. m. ligustica was investigated. Twelve types of sensilla were recorded on the worker antennae; placodea, basiconica, trichodea types (A, B, C and D), ampullaceal, coeloconica, coelococapitular, non-innervated hair seta, campaniformia and sensilla chaetica. The latter is recorded for the first time on antennae of A. mellifera. The number and distribution of the various types of sensilla are recorded. Sensilla trichodea were found most frequently and were present on all the antennal segments. Sensilla placodea were present on the distal eight flagellomeres. Sensilla ampullaceal and sensilla coeloconica were present on the distal five while sensilla campaniformia were confined to the distal seven flagellomeres. The barbs carried on the lancets of sting differ in numbers among the workers of the three subspecies; 10, 9 and 7 in A. m. lamarckii, A. m. carnica and A. m. ligustica, respectively. Depending on morphometrical analysis, a dendrogram separated the Egyptian subspecies from the other two subspecies with a highly genetic distance of 0.25 between them. The Italian and the Carniolan subspecies were grouped into one main cluster with a genetic distance of 0.01 between them.

Sensilla on antenna, ovipositor and leg of Eriborus applicitus (Hymenoptera: Ichneumonidae), a parasitoid wasp of Holcocerus insularis staudinger (Lepidoptera: Cossidae)

AbstractEriborus applititus Sheng & Sun (Hymenoptera: Ichneumonidae) is a specialist parasitoid of the small carpenter moth Holcocerus insularis Staudinger (Lepidoptera: Cossidae). Each year damages to trees caused by H. insularis lead to extensive economic and ecological losses. E. applititus is thus a promising candidate for use as a biocontrol agent against H. insularis. To investigate the means by which E. applititus locates and parasitizes H. insularis, we used scanning electron microscopy to determine the morphology and distribution of sensilla on antenna, ovipositor and leg of male and female E. applititus. Eight different sensilla types were found: sensilla chaetica, sensilla trichodea, sensilla placodea, sensilla basiconica, sensilla coeloconica, sensilla pit basiconica, sensilla campaniformia and Böhm's bristles. The sensilla types were differently distributed in the three organs. In addition, differences between sexes were found in the distribution of sensilla trichodea type 2, sensilla placodea and sensilla chaetica type 4. Putative functions of the sensilla are discussed based on the morphological and location data and on previous research. Chemosensitive sensilla are putatively involved in host detection, pheromone detection and host discrimination processes. Mechanoreceptive sensilla likely function as vibrational sensors and are thought to be critical for accurate ovipositor positioning.

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.

Biomorphometric characteristics of different types of sensilla detected on the antenna of Helicoverpa armigera by scanning electron microscopy

A morphometric study on H. armigera antenna showed four styles of sensilla, i.e., styloconica, chaetica, coeloconica, and trichodea, and their numbers were estimated. Sensilla trichodea detect inter and intraspecific communication signals and was the most numerous. They were divided into three types: type I, the longest, with a length of 34.04±3.16μm and about 2.16 to 2.42μm in diameter at its base; 2) type II, intermediate, with a length of 22.58±0.77μm and basal diameter of 1.8–2.52μm; 3) type III, the shortest sensilla trichodea, with a length of 7.62±0.4μm and a range in diameter similar to that of type II. The length of the female sensilla trichodea was longer than that of the male. The total number of sensilla trichodea was estimated to be 7520 on the antenna of the female, and 6831 on the male antenna. The lengths of the sensilla trichodea type I and type III were significantly different on male (t=4.6881, P=0.0034) and female antenna (t=18.9852, P=0.0001). An estimation of the predicted surface area of the most numerous type I on sampled segments between the 12th and 20th segments from a female of H. armigera showed a surface area of 5×103μm2 and a sensillar density of 38sensilla/103μm2. The fraction of sensilla-occupied surface area was 0.4μm2.

Distribution and morphometric studies of flagellar sensilla in Emphorini bees (Hymenoptera, Apoidea)

The tribe Emphorini is a group of pollen-collecting solitary bees with a geographical distribution restricted to the western hemisphere. Most of the Emphorini bees collect Page 10 linepollen from a few specific plant families and display specialized behaviors for constructing their nests. Insect sensilla are the basic structural and functional units of cuticle receptors, serving mainly mechano- and chemo-receptor functions. The external morphology of the antennal sensilla has been well characterized in species of different families of Apoidea, however there is scarce information about this issue in solitary bees of the family Apidae. For a better understanding of the association between the external sensory system and several types of behaviors which emerged along the evolutionary history of bees, it is important to characterize the antennal receptors in several representative species of this tribe.The distribution of the antennal sensilla on the dorsal flagella of 18 taxa was studied in insects of both sexes, using light and scanning electron microscopy. There were six types of sensilla and setae on the antennae, which were identified as sensilla placodea, trichodea, basiconica, coeloconica, coelocapitular and ampullacea. The sensilla trichodea were classified into subtypes, A, B, C-D. Sensilla subtype A were the most abundant sensilla and were distributed over the entire antennae, while sensilla placodea and sensilla trichodea type B, showed a restricted distribution on specific areas of the flagella. We have recognized four patterns of spatial distribution of setae on dorsal flagella. Species having setae on the distal part of the flagellomeres tended to contain a low density of sensilla trichodea type A. Females showed a higher number of sensilla subtypes B and C-D than males; instead sensilla trichodea A were more abundant in males. No significant difference was found in the number of sensilla placodea, ampullacea, coeloconica and coelocapitular. Sensilla basiconica were found only in females. Our results showed that gustative and tactile sensilla were more abundant in female bees, as well as, olfactory receptors predominate in the antennal system of males. The possible coevolution of flagellar sensilla in males and females of solitary bees is discussed in light of previous reports. Patterns of distribution of setae determine the relative abundance of the types of sensilla in the flagellum.

Lateralization in the Invertebrate Brain: Left-Right Asymmetry of Olfaction in Bumble Bee, Bombus terrestris

Brain and behavioural lateralization at the population level has been recently hypothesized to have evolved under social selective pressures as a strategy to optimize coordination among asymmetrical individuals. Evidence for this hypothesis have been collected in Hymenoptera: eusocial honey bees showed olfactory lateralization at the population level, whereas solitary mason bees only showed individual-level olfactory lateralization. Here we investigated lateralization of odour detection and learning in the bumble bee, Bombus terrestris L., an annual eusocial species of Hymenoptera. By training bumble bees on the proboscis extension reflex paradigm with only one antenna in use, we provided the very first evidence of asymmetrical performance favouring the right antenna in responding to learned odours in this species. Electroantennographic responses did not reveal significant antennal asymmetries in odour detection, whereas morphological counting of olfactory sensilla showed a predominance in the number of olfactory sensilla trichodea type A in the right antenna. The occurrence of a population level asymmetry in olfactory learning of bumble bee provides new information on the relationship between social behaviour and the evolution of population-level asymmetries in animals.

Antennal morphology and sensilla ultrastructure of Dendroctonus valens LeConte (Coleoptera: Curculionidae, Seolytinae), an invasive forest pest in China

Dendroctonus valens LeConte, an invasive forest pest, is highly dependent on its olfactory system for activities such as host seeking, mating, oviposition and population aggregation. The antennae are the primary olfactory organs in bark beetles. We describe four morphological types of sensilla on the antenna of D. valens: (1) 3 subtypes of sensilla trichodea located at the apex and lateral surface of the club. Sensilla trichodea types 1 and 3 were innervated by 5 and 13 dendrites, respectively. Sensilla trichode type 2 was not found dendrites in a lumen, (2) sensilla chaetica found on the scape and funicle and innervated by 7 dendrites, (3) a pair of sensilla basiconica distributed primarily on the three sensory bands, each innervated by 2 dendrites at the base, and (4) one fluted cone type of grooved peg dispersed throughout the sensory bands. The possible functions of these sensilla are discussed in relation to their morphology and ultrastructure.

Antennal sensory receptors of Pteromalus puparum female (Hymenoptera: Pteromalidae), a gregarious pupal endoparasitoid of Pieris rapae

The external morphology of the antennal sensilla of Pteromalus puparum females (Hymenoptera: Pteromalidae) is described using scanning electron microscopy. The antennae of P. puparum females are geniculate in shape, formed from a large, cylindrical scape with a basal radicel fitting into the antennal socket, a shorter, barrel-shaped pedicel and a flagellum composed of 12 subsegments. Eight morphologically distinct types of sensilla were found on the female antennae. These are: nonporous sensilla trichodea types 1 and 2, which are putative mechanosensilla, nonporous sensilla chaetica, which may function as proprioceptors, uniporous sensilla trichodea types 3 and 4, which are presumably contact chemosensilla, basiconic capitate peg sensilla, which probably function in thermo-hygro reception, multiporous sensilla trichodea, and multiporous sensilla placodea which are all presumed to be olfactory sensilla.

Antennal structure and oviposition behavior of thePlutella xylostella specialist parasitoid:Cotesia plutellae

Although several species of the genus Cotesia are used in biological control programs against insect caterpillars throughout the world, little is known of their oviposition behavior. We describe here the types and distribution of antennal sensilla in Cotesia plutellae, a larval parasitoid of Plutella xylostella, and we analyze its oviposition behavior. Seven types of sensilla were found on both males and females. Only sensilla trichodea type II, with a putative contact chemoreceptive function, was significantly more abundant in females than in males, and its morphology and position on antennomeres were linked to the antennation behavior used by females during host search. We conclude that gustatory stimulus following antennal contact is probably the key stimulus inducing oviposition behavior. The sensilla type assumed to be implied in oviposition behavior was present in C. plutellae but not in two closely related species (C. glomerata and C. rubecula), which is discussed.

Antennal sensilla of the ground beetle Bembidion properans Steph. (Coleoptera, Carabidae)

The arrangement of antennal sensilla was studied in female and male ground beetles Bembidion properans Steph. (Coleoptera, Carabidae) using scanning electron microscopy. The filiform antennae, 1.8–1.9mm in length, consist of the scape, pedicel and nine flagellomeres. In both sexes, three types of sensilla chaetica, two types of sensilla trichodea, six types of sensilla basiconica, one type of sensilla coeloconica and one type of sensilla campaniformia were distinguished. The possible function of the sensilla is discussed and three types of sensilla are considered olfactory, sensilla trichodea type 2 and sensilla basiconica types 1 and 2. Olfactory sensilla form dorsal and/or ventral sensillar fields on the flagellomeres and occur sparsely or not at all outside these areas. No sexual differences in the types, number and distribution of antennal sensilla were found.