Morphology and distribution of sensilia on the cephalic appendages,tarsi and ovipositor of the European sunflower moth,Homoeosoma nebulella Den. & Schiff. (Lepidoptera : Pyralidae)

Sensilla on male and female antennae, mouthparts, tarsi and on the ovipositor of the European sunflower moth, Homoeosoma nebulella (Lepidoptera : Pyralidae) have been investigated by means of scanning electron microscope. The antennal flagellum bears multiporous sensilla (trichodea, basiconica, auricillica, coeloconica) and uniporous sensilla (chaetica, styloconica). A sexual dimorphism is found in the numbers of sensilla trichodea (8300 in males and 6000 in females) and sensilla basiconica (1150 in females and 650 in males). The proboscis has uniporous s. styloconica, multiporous s. basiconica (described for the first time in Lepidoptera), aporous s. chaetica, and some rare uniporous s. basiconica in the food channel. The labial palp-pit organ houses multiporous s. coeloconica, while the maxillary palps have aporous sensilla. Tarsi of both sexes possess one type of aporous s. chaetica and 2 types of uniporous s. chaetica. There is no significant difference in the distribution of tarsal sensilla between males and females. The surface of each lobe of the ovipositor is covered by 3 types of aporous s. trichodea of different lengths and about 60 multiporous s. basiconica, sensilla unusual on the ovipositor of Lepidoptera. The role of sensilla in the oviposition site selection is discussed.     

Antennal sensilla of the click beetle,limonius aeruginosus (OLIVIER) (COLEOPTERA: ELATERIDAE)

Antennal sensilla typology, number and distribution of the click beetle Limonius aeruginosus (Olivier) (Coleoptera: Elateridae) were studied using scanning electron microscopy. The serrate antennae of both sexes of L. aeruginosus consist of the scape, pedicel and of the flagellum which is composed of 9 flagellomeres. In both sexes, 5 types of sensilla basiconica, 1 type of sensilla trichodea, 1 type of sensilla chaetica, 1 type of sensilla campaniformia and Böhm sensilla were distinguished. No remarkable sexual differences in the types, numbers and distribution of sensilla were found on the antennae, except for the sensilla basiconica type II. The average number of sensilla basiconica type II on the antennae of the male beetle surpassed that on the antennae of the female beetle (3562 and 108 pegs, respectively). It is suggested that this type of sensilla on the male beetles antennae is responsible for the reception of the sex pheromone produced by the female beetle.     

Morphology,distribution, and ultrastructural differences of sensilla trichodea and basiconica on the antennae of the oriental fruit moth,Grapholitha molesta (Busck) (Lepidoptera : Tortricidae)

Three types of sensilla trichodea and 2 types of the shorter sensilla basiconica were identified on the antennae of Grapholitha molesta (Lepidoptera : Tortricidae). All possess a non-flexible base and cuticular pores. The 3 types of s. trichodea (A, B, and C) have similar dimensions and surface sculpturing, but differ in their ultrastructure and in being located in either the scale-covered or scale-free regions of the antennae. The 2 types of, s. basiconica (I and II) differ from one another in length, surface sculpturing, and location. Ultrastructural differences in wall thickness, number of neurons, number of dendrites and their branches and in the electron density of dendrites between the 3 types of s. trichodea and s. basiconica type I are described.All s. trichodea in the scaled region and 5 – 6% of those in the scale-free region were type A, while types B and C occurred only in the scale-free regions. Males had a significantly greater number of s. trichodea than females (P < 0.001). The increased number occurred mainly in the scale-covered regions of the antennae, where males had 2200 more s. trichodea (all of type A) than females. In the scale-free region however, males only had 700 more s. trichodea (mainly types B and C) than females. Type A s. trichodea in the scale-covered region of the flagella of male G. molesta is a most likely sensilla for tests to confirm its role in the perception of female produced pheromone.     

Antennal sensilla of male and female Telenomus reynoldsi gordh and coker (Hymenoptera : Scelionidae)

Sensilla on the antennae of both sexes of Telenomus reynoldsi (Hymenoptera : Scelionidae) were studied with the scanning electron microscope to determine their structure and possible function in mating and host recognition. Two types of setiform sensilla occur: curved, grooved sensilla trichodea and erect, stout sensilla chaetica. Horn-like sensilla trichodea curvata are abundant on the male antennae, but are less abundant and only present dorsally on the female. Sensilla basiconica are unique to the ventral surface of the apical 4 segments of the female antennae. Sensilla styloconica are located on A4 and A10 of the female and A7 and A9 of the male. Multiporous grooved sensilla are present on A4, A6, and A11 of the female and A4 and A6-A11 of the male. A possible sex gland is located on the venter of A5 of the male. The functions of sensilla trichodea curvata and sensilla basiconica in courtship and host recognition, respectively, are hypothesized by correlation with behavioral observations.     

Sensilla of the antennal flagellum in Pseudaletia unipuncta (Haw.) (Lepidoptera: Noctuidae)

Seven sensilla were observed on the antennal flagellum of both sexes of Pseudaletia unipuncta (Haw.) (Lepidoptera : Noctuidae): chaetica Type I and Type II), styloconica, coeloconica, trichodea (Type 1a, b, c and Type II a, b), auricillica, nonporous and squamiformia. The major sexual dimorphism noted was the presence of Type la trichodea on the male antennae, suggesting that this sensillum may contain the receptor sites for the female sex pheromone. Differences in the size of sensilla coeloconica, auricillica and trichodea (Types Ib, IIb) were noted between sexes, being larger in females. Adults obtained from larvae fed on artificial diet generally had longer antennae and sensilla than those fed on young oat plants.     

中红侧沟茧蜂触角感受器的扫描电镜观察

利用扫描电镜对中红侧沟茧蜂Microplitis mediator的触角感受器进行了观察,发现了6个类型的感器,分别为毛形感器、板形感器、刺形感器、钟形感器、锥形感器、腔锥形感器。其中,毛形感器具有2种形态,锥形感器具有4种形态。钟形感器仅分布于雌蜂的触角上,锥形感器Ⅲ和Ⅳ仅分布于雄蜂的触角上。结合感受器的形态、分布和已报道的触角电位反应数据,对各感受器的功能进行了推测。     

红火蚁触角及其上感受器的扫描电镜观察

应用扫描电镜对采自我国广东吴川和广西南宁的红火蚁Solenopsis invicta Buren工蚁、有翅雌蚁和雄蚁触角的形态和感受器类型进行了研究。结果表明,工蚁、雌蚁和雄蚁的触角存在着较大的差异。工蚁和雌蚁的触角为膝状,末端2或3节膨大为棒状,雌蚁的触角11节,比工蚁(10节)的多1节。雄蚁的触角为线状,12节,末端没有棒状结构。工蚁和雌蚁的触角上共有7种感受器,分别为毛形、曲毛形、锥形、腔锥形、坛形、刺形感受器和Böhm氏鬃毛,前6种感受器大多集中在触角末端的棒节,棒节以外的各鞭节上主要是毛形感受器,Böhm氏鬃毛则分布于柄节和梗节的基部,鞭节上无此感受器。雄蚁触角上也有7种感受器,但其分布与工蚁的有较大差异,Böhm氏鬃毛的分布与工蚁和雌蚁的相同,锥形感受器分布在末端2节,坛形感受器分布在末端3节,其余的4种感受器较为均匀地分布在各鞭节,而不是聚集在端节。另外,新发现雄蚁中存在一种与已知的毛型感受器不同的超短毛状感受器,定名为超短毛感受器。最后,对红火蚁的触角及感受器在蚁群社会性行为中的作用进行了讨论。     

桑天牛头部附器感器的扫描电镜观察

利用扫描电镜观测桑天牛Apriona germari(Hope)成虫的触角、下颚须和下唇须上感器的分布及超微结构。结果表明,雌、雄桑天牛触角上共存在6种感器,即毛形感器、锥形感器、刺形感器、芽形感器、鳞形感器和棒形感器,其中锥形感器分5种亚型,刺形感器分2种亚型,且部分感器在雌雄成虫触角上的分布模式及数量存在差异,如棒形感器及角锥形感器丛模式仅在雄虫触角上发现,而雌虫触角上的细锥形感器和耳锥形感器多于雄虫,芽形感器少于雄虫;下颚须和下唇须存在5种感器,即毛形感器、刺形感器、末梢锥形感器、钟形感器和隙缝感器,各种感器在雌、雄天牛下颚须和下唇须上的分布和数量无明显的区别。     

属模巨齿蛉成虫感器的超微形态

为了解属模巨齿蛉成虫多个部位感器的超微结构及其对生命活动的影响,本文对属模巨齿蛉成虫的触角、大颚、翅缘和生殖器4个部位进行了电镜扫描。研究发现,触角有7种感器,分别是毛形感器Ⅰ型、Ⅱ型、Ⅲ型、Ⅳ型、腔锥感器、锥形感器、柱形感器;大颚有3种感器,分别是腔锥感器、锥形感器、刺形感器;翅缘有4种感器,分别是毛形感器Ⅱ型、Ⅲ型、Ⅳ型、腔锥感器;雌性成虫生殖器有7种感器,分别是毛形感器Ⅱ型、Ⅲ型、Ⅳ型、Ⅴ型、Ⅵ型、锥形感器、钟形感器。柱形感器是触角的特殊感器,钟形感器是雌性成虫生殖器的特殊感器。毛形感器是触角、翅缘和生殖器主要感器,而大颚上没有毛形感器。触角和生殖器上的感器类型最多,且分布最密集,这与触角和生殖器对成虫的交配、产卵行为具有重要作用相吻合。     

Scanning Electron Microscopy Study of the Antennal Sensilla of <Emphasis Type="Italic">Monema flavescens</Emphasis> Walker (Lepidoptera: Limacodidae)

Monema flavescens Walker (Lepidoptera: Limacodidae) is a serious polyphagous defoliator. Using scanning electron microscopy, the external morphology of the antennal sensilla of this pest was examined for a better understanding of the mechanisms of insect-insect and insect-plant chemical communications. The antennae of M. flavescens were filiform in shape, and 11 morphological types of sensilla were found in both sexes. Six types of likely chemosensory sensilla were identified: uniporous sensilla chaetica, multiporous sensilla trichodea, and four types of multiporous sensilla basiconica. The sensilla identified as likely mechanoreceptors included two subtypes of aporous sensilla chaetica, aporous sensilla coeloconica, aporous sensilla styloconica, and Böhm’s bristles, whereas the position of the antennae was monitored by Böhm’s bristles.     

Sensory Organs on the Antennae of Micropterix calthella L. (Lepidoptera, Micropterigidae)

Antennal sensilla of Micropterix calthella were studied with the scanning electron microscope to determine their morphological types, relative abundance, distribution, location and possible functions. Of the 12 types occurring in both male and female moths, seven are found in most higher Lepidoptera: sensilla trichodea, multiporous s. basiconica, s. coeloconica, s. styloconica, s. chaetica, s. campaniformia and Böhm's bristles. Two types (uniporous s. basiconica and cupuliform organs) are found only in a few families. Three structures are peculiar to Micropterix : ascoïd sensilla, multiporous s. placodea and circular organs. All types of sensilla have characteristic distribution and location pattern similar in both sexes.     

亚洲玉米螟成虫触角的扫描电镜观察

对亚洲玉米螟成虫触角的外部形态结构在扫描电镜下作了观察.触角由柄节、梗节和62—67个鞭节组成,触角背面被鳞片覆盖,绝大部分触角感器位于触角的腹面和侧面.所有鞭节的表皮上都有连续的网纹结构,但在柄节和梗节的表皮上则无.在雌雄蛾的触角上都可以找到以下七种感器,即栓锥感器、腔锥感器、锥形感器(即B?hm氏鬃毛)、刺形感器、耳形惑器、鳞形感器和毛形感器.毛形感器数目最多,并根据其形状和表面细微结构分为两种类型:A型和B型.除锥形感器外,所有的感器都分布在触角鞭节的网纹区上.对此昆虫的触角两性差异进行了详细的讨论.     

Ultrastructure of the antennal sensilla of Alabama argillacea (Hübner, 1823) (Lepidoptera: Erebidae)

Insects have several types of sensilla, the characterization of which has been fundamental to understanding the mechanisms of sensory perception in different species. This study aimed to describe the ultrastructure of the sensilla present on the antennae of Alabama argillacea (Hübner, 1823) (Lepidoptera: Erebidae), an important pest of cotton (Gossypium hirsutum L.) crops, as well as their possible variation between sexes. To do this, the antennae of males and females of A. argillacea were analyzed using scanning electron microscopy. Sensilla morphometry was assessed using photomicrographs, from which the lengths and basal and apical diameters of sensilla were measured using the ImageJ program. Seven types of sensilla were identified on the antennae of A. argillacea: sensilla trichodea, sensilla chaetica, sensilla auricillica, sensilla coeloconica, sensilla styloconica, sensilla basiconica, and sensilla Böhm bristles. Differences between the sensilla of males and females were found in their lengths and basal diameters in the distal and proximal regions. This suggests that sensilla functionality may not only vary from one species to another, but also between sexes within the same species. Thus, further transmission electron microscopy and single sensillum recording studies may provide more detailed information on the sensilla of A. argillacea and their functions.     

Atlas of olfactory organs of Drosophila melanogaster: 1. Types,external organization,innervation and distribution of olfactory sensilla

The third antennal segment (funiculus) and the maxillary palp are the main and accessory olfactory sense organs of Drosophila melanogaster. Cryofixed antennae and palps revealed a superior preservation of the sensory dendrites and other cellular details as compared to conventional chemical fixation. Extensive cross-section series through funiculus and palp were studied in order to obtain as complete an evaluation as possible of the sensillar complement on these appendages. About 75% of all sensilla on the male and female funiculus were individually studied and their position on the antennal surface mapped. Dimensions of the cuticular apparatus of the various types of sensilla are provided as well as the number of innervating receptor neurons. Particular attention has been paid to the cuticular pores important for stimulus transport and to the sensory dendrites. On the funiculus surface, all sensilla have multiple wall pores: sensilla (s.) trichodea and s. basiconica are single-walled, s. coeloconica are double-walled. The distribution of s. trichodea and s. basiconica follows opposing gradients along a diagonal axis parallel to the axis of the arista from proximo-medial to disto-lateral. In this disto-lateral direction the density of s. trichodea increases while that of the s. basiconica decreases. S. trichodea occur in three subtypes with one, two or three receptor neurons. Basiconic sensilla can be subdivided into three subtypes of large s. basiconica (with two or four receptor neurons), three subtypes of thin s. basiconica (with mostly two, rarely four neurons), and one subtype of small s. basiconica with two receptor neurons. Large s. basiconica occur only in the most proximal region (the ‘LB-zone’); thin s. basiconica are most common in a belt that borders the LB-zone distally, while small s. basiconica are most numerous even further distally along the mentioned diagonal axis in between the s. trichodea. S. intermedia are single-walled, multiporous sensilla which combine features of s. trichodea and s. basiconica; they are found in two subtypes with two or three receptor neurons, in the same region where s. trichodea abound. The s. coeloconica are irregularly distributed over the funicular surface, and occur in two subtypes with two or three receptor neurons. Sexual dimorphism on the antenna is moderate, the female funiculus is a bit longer and carries a larger number of small s. basiconica and large s. basiconica of the LB-I subtype; the male funiculus, however, has more s. trichodea than the female. On the maxillary palp, besides mechanoreceptive s. chaetica, there are only s. basiconica with two receptor neurons. According to the fine structure of their sensory dendrites, three subtypes can be discriminated which are distributed in a random pattern. The functional significance of the described structures and distribution awaits future immunocytochemical and electrophysiological experiments.     

Flagellar Sensilla of Sphecodes Bees (Hymenoptera, Halictidae)

The antenna of Sphecodes bees were investigated as regards the type and distribution of the sensilla. Eleven species originating from Sweden were used. Totally 325 specimens were studied. The distribution of sensilla placodea and sensilla trichodea on the antennal segments were studied in the light stereomicroscope. One to three antennae per species were also examined by SEM. The following types of sensilla were found: s. placodea; pit organs; s. campaniformia; s. basiconica; s. trichodea A, B and CD; and setae. The distribution of sensilla, especially s. placodea and s. trichodea A, was found to be species-specific in the male sex and their diagnostic value in taxonomy is stressed. In the female sex no specific characteristics were found, although two groups could be distinguished.     

Antennal sensilla of the ground beetle Bembidion lampros Hbst (Coleoptera, Carabidae)

Antennal sensilla typology, number and distribution pattern were studied in the ground beetle Bembidion lampros Hbst (Coleoptera, Carabidae) using scanning electron microscopy. The 1.6–1.8 mm long filiform antennae of both sexes consist of the scape, pedicel and of the flagellum composed of nine flagellomeres. In both sexes, three types of sensilla chaetica, two types of sensilla trichodea, five types of sensilla basiconica, one type of sensilla coeloconica, one type of sensilla campaniformia and Böhm sensilla were distinguished. The possible function of the sensilla was discussed and three types of sensilla were considered as olfactory, sensilla trichodea type 2 and sensilla basiconica types 1 and 2. Olfactory sensilla occupy dorsal and/or ventral areas of the flagellomeres and occur sparsely (sensilla basiconica type 1) or not at all (sensilla basiconica type 2 and sensilla trichodea type 2) outside these areas. No remarkable sexual differences in the types, numbers and distribution of antennal sensilla were found.     

Mate recognition and antennal morphology of Octodonta nipae (Coleoptera: Chrysomelidae) adults

The nipa palm hispid beetle, Octodonta nipae (Maulik) has been killing palm trees since its introduction into Hainan province, China, from Malaysia in 2001. It continues to spread within Hainan province, northeast to Fujian province, and northwest to Yunnan province within China. Knowledge on signals involved in mate location and recognition could help develop effective integrated pest management programs. In the present study, we first experimentally proved that antennae were essential in success of O. nipae mating. We then excised various segments/flagellomeres of adult male and female antennae and observed their mating behavior. Results revealed that the 5th to 9th flagellomeres, especially those of males, were important for the mating success. Finally, in an attempt to elucidate the types of antennal sensilla accountable for the mating success, morphology of O. nipae antennae was studied in detail with scanning electron microscopy. Six types of sensilla were distinguished: aporous sensilla trichodea (T1), multiporous sensilla trichodea (T2), aporous sensilla chaetica (Ch1), uniporous sensilla chaetica (Ch2), multiporous sensilla basiconica (B), and Böhm sensilla (Bm). Aporous sensilla trichodea is the most abundant; multiporous sensilla trichodea and sensilla basiconica are considered as olfactory receptors, and uniporous sensilla chaetica as gustatory receptor. Importance of flagellomeres 5–9 in mating success seemed to correspond to the abundance of sensilla on these segments.     

The antennae of neopseustid moths: Morphology and phylogenetic implications, with special reference to the sensilla (Insecta, Lepidoptera, Neopseustidae)

The antennae of Lepidoptera Neopseustidae were examined with the scanning electron microscope. The studied species, Nematocentropus cfr. omeiensis, Neopseustis meyricki, Synempora andesae, Apoplania valdiviana and Apoplania penai possess nine types of antennal flagellum sensilla: multiporous large sensilla basiconica, multiporous thin sensilla basiconica, multiporous small sensilla basiconica, multiporous sensilla trichodea, multiporous sensilla coeloconica; uniporous sensilla chaetica; aporous sensilla chaetica, aporous stylus-shaped sensilla chaetica, aporous sensilla styloconica.The multiporous sensillum type here termed “multiporous large sensillum basiconicum” is unknown from other Lepidoptera and probably constitutes an autapomorphy of the family Neopseustidae. This sensillum type is remarkable by having a single base in female Apoplania and Synempora while in male Apoplania it has a bifid or trifid base, and in male Synempora it is composed of two or three incompletely separated hairs. This may be the first recorded example of a sexually dimorphic lepidopteran sensillum type. The stylus-shaped sensillum chaeticum is a primitive type which occurs only in some lower Lepidoptera.     

Antennal sensilla of male Lophocorona pediasia Common 1973 and their phylogenetic implications (Lepidoptera: Lophocoronidae)

The male antennae of Lophocorona pediasia reveal seven types of sensilla: multiporous sensilla trichodea, multiporous sensilla basiconica of subtypes 1 and 2, multiporous sensilla auricillica, aporous sensilla styloconica, multiporous sensilla coeloconica and aporous Böhm’s sensilla. All these sensillum types are present in the higher Lepidoptera. The existence of sensilla auricillica, hitherto denied by several authors, is demonstrated in this study. Typically, they are located on the distal edge of the flagellomeres as in most Lepidoptera. Therefore, their so-called absence must no longer be regarded as an autapomorphy of the Lophocoronidae. Their presence is a common characteristic of all «Dacnonypha», which include, apart from the Lophocoronidae, the Eriocraniidae and the Acanthopteroctetidae. Their number in L. pediasia is smaller than in these two families and more in accordance with the condition found in higher Lepidoptera, suggesting a more advanced position of the Lophocoronidae. The presence of very numerous sensilla basiconica is a possible autapomorphy of the family.     

Sensilla of Carabus (Isiocarabus) fiduciarius saishutoicus Csiki (Coleoptera : Carabidae)

Sensilla on the antenna of the ground beetle, Carabus (Isiocarabus) fiduciarius saishutoicus Csiki (Coleoptera: Carabidae), were investigated using scanning electron microscopy. In both sexes, 5 types of sensilla trichodea, 7 types of sensilla basiconica, 1 type of sensilla ampullacea, and 2 types of sensilla campaniformia are distinguished. No sexual differences in the types and distribution of sensilla are found on the antenna, except a ventral, depressed, hairless region of the male. Various types of sensilla present on the mouthparts, head, pronotum, elytron, hindwing, legs, abdominal tergites and sternites, aedeagus, and ovipositor are also described.