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.     

小菜蛾成虫喙管感器的超微结构及其神经元中枢投射

【目的】明确小菜蛾Plutella xylostella成虫喙管感器的形态结构及感器神经元的投射。【方法】利用扫描电子显微镜观察小菜蛾成虫喙管结构和感器,利用神经回填技术和激光共聚焦显微镜观察喙管感器神经元在脑部的投射。【结果】小菜蛾成虫喙管上存在毛形感器(两种亚型)、腔锥形感器、锥形感器、刺形感器和栓锥形感器5种不同类型的感器。毛形感器表面光滑,分布于外颚叶外侧,可分为毛形感器Ⅰ型和Ⅱ型两种亚型,其中Ⅰ型比Ⅱ型长;锥形感器分布于喙管外表面,由一个感觉锥和一个短的圆形基座组成;腔锥形感器仅分布于食管内侧,只有一个粗短感觉锥而无基座;刺形感器由一个细长的感觉毛和一个圆形基座组成,表面无孔,分布于喙管的外表面;栓锥形感器是昆虫喙管上最典型的感受器,集中分布于喙管顶端区域,感器顶部凹腔伸出一个单感觉锥。此外,喙管上的感觉和运动神经元投射到初级味觉中枢咽下神经节。【结论】本研究阐明了小菜蛾成虫喙管感器的类型、分布和形态特征及其感器神经元在脑部的投射形态,为深入了解小菜蛾喙管感器的生理和功能奠定了基础。     

Proboscis sensilla in Vanessa cardui (Nymphalidae, Lepidoptera): functional morphology and significance in flower-probing

 Morphology and distribution of the proboscis sensilla in Vanessa cardui have been investigated in order to contribute to the understanding of flower-probing behaviour in butterflies. The proboscis has a bend region approximately one-third of the length from the base. A short tip region is characterized by rows of intake slits leading into the food canal. Along the dorsal, lateral and ventral sides of the proboscis, sensilla trichodea, sensilla basiconica and sensilla styloconica are distributed in varying patterns depending on their distance from the b ase. The medial food canal bears one longitudinal row of sensilla basiconica only. The bristle-shaped sensilla trichodea are longer in the proximal region of the proboscis and become gradually shorter towards the tip. They are most frequent in number near to the bend region and near the beginning of the tip region. Sensilla basiconica arranged in longitudinal rows increase in number the more distal they are on the proboscis. The tip region is characterized by rows of sensilla styloconica on the dorsal side whereas the sensilla trichodea are mostly restricted to the ventral side. The ultrastructure suggests that the aporous sensilla trichodea function as mechanosensilla while the uniporous sensilla basiconica act as contact chemosensilla. The sensilla styloconica are regarded as bimodal contact chemo/mechanosensilla since their sensory cones are equipped with a single terminal pore and a tubular body at the base. The mouthpart sensilla appear to provide tactile cues on the positioning of the proboscis and on the degree of its insertion into a floral tube. Furthermore, they receive chemical stimuli on the availability of nectar and on the immersion status of the food canal. Accepted: 12 September 1997     

Sensilla on the larval antennae and mouthparts of the european sunflower moth,Homoeosoma nebulella Den. and Schiff. (Lepidoptera : Pyralidae)

Sensilla on the larval antennae and mouthparts of Homoeosoma nebulella (Lepidoptera : Pyralidae) were examined with a scanning electron microscope. The antenna possesses 2 aporous sensilla chaetica, one aporous sensillum styloconicum, 3 large multiporous sensilla basiconica, and 3 small multiporous s. basiconica. The labrum bears 12 aporous s. chaetica and the epipharynx has 6 aporous flattened s. chaetica and 4 epipharyngeal sensilla. It is the first time that more than 2 epipharyngeal sensilla have been reported in caterpillars. The mandible possesses 4 aporous s. chaetica. Each galea bears 2 uniporous s. styloconica, 2 small aporous s. basiconica, one s. campaniformium and 3 aporous s. chaetica. Each maxillary palp bears a distal group of 8 uniporous s. basiconica, one large s. digitiformium and one pore plate. Minute grooves exist on the s. digitiformium. Each labial palp possesses one aporous s. chaeticum and one aporous s. styloconicum. An attempt has been made to identify the function of sensilla by comparing them with those of other larvae.     

Sensillum types on the proboscis of the Lepidoptera: a review

The external surface of lepidopteran proboscides may bear six morphological types of sensilla: chaeticum, basiconicum, styloconicum, coeloconicum, filiformium, and campaniformium, with the first three types being the most common. There are four types of pore-system: aporous, uniporous, multiporous, and uniporous-multiporous. Sensilla chaetica and campaniformia are aporous sensilla with a tactile or a proprioceptive function, respectively. Aporous sensilla filiformia are probably vibroreceptors. Uniporous sensilla with a gustative function exist in sensilla basiconica, styloconica and coeloconica. Multiporous sensilla were found in long sensilla basiconica and seem rare. Uniporous-multiporous sensilla are relatively common and are to be found both in sensilla styloconica (Arctiidae, Noctuidae) and in sensilla basiconica (Adelidae, Pyralidae, Arctiidae, Noctuidae). It is difficult to establish their function (gustative or olfactive). More extensive research would make it possible to discover them in other families. Only gustative uniporous sensilla basiconica exist in the food canal. The morphology of the proboscis and the distribution of sensilla are adapted to food habits.     

Reproductive strategies and parasitization behavior of Ageniaspis citricola, a parasitoid of the citrus leafminer Phyllocnistis citrella

We describe the number, distribution, and function of sensilla located on different organs of Lobesia botrana (Lepidoptera: Tortricidae) females using scanning electron microscopy, selective staining, and contact electrophysiology. The tarsi of the prothoracic legs bear contact chemo‐mechanoreceptor sensilla chaetica (5–13 per tarsomere), arranged in rings mainly concentrated on ventral surfaces, and different mechanosensory structures (sensilla chaetica, sensilla squamiformia, sensilla campaniformia, and spines). A single contact chemo‐mechanoreceptor sensillum chaeticum is present between the claws on the pretarsus. The ventral surface of the ovipositor lobes is covered with numerous mechanosensory sensilla chaetica of different types, out of which 10 have a contact chemosensory function. Putative contact chemo‐mechanoreceptor sensilla were also observed on the proboscis and antenna. Longitudinal rows of alternated sensilla styloconica and basiconica are present on the distal part of the proboscis, and rings of sensilla chaetica are present at the antennal tip. The sensilla on these body parts may play different roles in the selection of an oviposition site.     

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.     

灰茶尺蠖成虫触角及幼虫头部感器超微结构

【目的】明确灰茶尺蠖Ectropis grisescens成虫触角及幼虫头部感器的种类、形态、数量和分布,以探讨灰茶尺蠖的行为机制。【方法】利用扫描电镜技术观察灰茶尺蠖雌、雄成虫触角和5龄幼虫头部感器的超微结构。【结果】灰茶尺蠖成虫触角上分布有8种感器,分别是栓锥形感器、耳形感器、毛形感器(Ⅰ-Ⅳ)、B?hm氏鬃毛、腔锥形感器(Ⅰ和Ⅱ)、鳞形感器、锥形感器(Ⅰ和Ⅱ)和刺形感器。其中,栓锥形感器仅分布在雌蛾触角上,耳形感器、毛形感器(STⅠ-Ⅲ)仅分布在雄虫触角上。5龄幼虫触角上着生1个栓锥形感器、1个锥形感器和2个刺形感器;上唇着生有6对刺形感器,内唇着生有3对刺形感器和1对指形感器;上颚基部外侧着生有2个刺形感器;下颚及下颚须着生有5个刺形感器、9个锥形感器和2个栓锥形感器;下唇须着生有1个锥形感器和1个刺形感器;吐丝器前端着生有1对刺形感器。【结论】灰茶尺蠖雌、雄成虫触角感器存在性二型性,且雄虫上感器种类和数量较多,据此推测雄虫感受寄主植物或性信息素的能力较强;幼虫头部感器具有嗅觉和味觉功能,在其判断食物的种类和适应性等生态行为中发挥重要作用。     

三种夜蛾成虫口器感器的超微形态

为确定不同种类夜蛾口器及其感器在超微结构上的差异, 采用扫描电子显微镜对棉铃虫Helicoverpa armigera (Hübner)、 烟夜蛾H. assulta (Guenée)和银纹夜蛾Argyrogramma agnata (Staudinger)3种鳞翅目(Lepidoptera)夜蛾科(Noctuidae)重要农业害虫雌、 雄成虫口器感器的超微形态进行了观察和比较。结果表明： 3种夜蛾雌、 雄成虫口器感器类型均无明显差异。棉铃虫和烟夜蛾口器感器在类型和形状上十分类似, 均具有毛形、 锥形和栓锥形感器; 喙管末端的栓锥感器粗、 密, 棱纹明显。银纹夜蛾口器感器与两种铃夜蛾区别明显, 除上述3类感器外, 还具有腔锥形感器; 其喙管末端的栓锥感器细、 疏, 棱纹不明显。结果显示口器感器可用于夜蛾的分类及亲缘关系研究。     

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.     

Antennal sensilla on cave species of Australian Paratemnopteryx cockroaches (Blattaria : Blattellidae)

The external morphology and distribution of antennal sensilla of cave-dwelling Australian cockroaches, Paratemnopteryx stonei (Races B and C), P. howarthi and P. sp. nov. (Blattaria : Blattellidae), are described using scanning electron microscopy. Eight major types of sensilla were found. Long and medium-length sensilla chaetica are deeply grooved mechano and contact chemo-receptors with a terminal pore; the long type forms 5–11% and the medium-length 7–22% of all sensilla. Sensilla trichodea type 1 are very slender, non-porous, and form 43–60% of all sensilla. Sensilla trichodea type 2 are stouter, shorter and have wall pores; they form 5–14% of the sensilla. Sensilla basiconica type B are very short, non-porous, inflexible-socket receptors that are known to be hygro- and thermo-receptors; they comprise less than 0.6% of the sensilla. Sensilla basiconica type Gl are short, grooved and have a terminal pore; they form 5–11% of all sensilla. Type G2 are longer with indications of a terminal pore and form 7–10% of the sensilla. Sensilla basiconica type P are short with wall pores, and they form 3–9% of the sensilla. Total sensillar numbers ranged from 5700–8900 for P. stonei, depending on the race and sex, 6950–9950 for P. sp. nov. and 11,700-15,100 for the smaller and possibly more epigean-related P. howarthi. Females had 700–3150 fewer sensilla than males. Comparisons are made between Paratemnopteryx and common epigean cockroaches in relation to sensillar types and numbers.     

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.     

斑鞘豆叶甲触角感器的超微结构

斑鞘豆叶甲是大豆苗期重要害虫,本文利用扫描电镜技术观察了斑鞘豆叶甲触角感器超微形态与分布。结果表明:斑鞘豆叶甲触角感器绝大部分着生于鞭节,在鞭亚节端部和末节凹陷区感器分布密集,类型较多。基于感器外部形态可分为8种类型:毛形感器Ⅰ型和Ⅱ型、刺形感器、锥形感器、指形感器、腔锥形感器、栓锥形感器Ⅰ型和Ⅱ型、钟形感器和B hm氏鬃毛。其中毛形感器数量最多,其次是锥形感器,钟形感器最少,仅分布于雄虫触角,还着生有大量表皮孔。雌、雄虫触角感器在形态、数量和分布上均存在差异,雄虫毛形和刺形感器显著长于雌虫,刺形感器端部膨大,两种感器的数量也明显多于雌虫;雌虫与雄虫相比末节背面也具感器密集的凹陷区,指形感器短于雄虫但数量显著多于雄虫。斑鞘豆叶甲触角感器种类丰富,分布密集,雌、雄虫感器存在明显的性二型现象,其结构和类型表现出种间分化特性。     

Ultrastructure of antennal sense organs of small ermine moths,Yponomeuta spp. (Lepidoptera : Yponomeutidae)

The ultrastructure of antennal sensilla was investigated in males and females of 5 European Yponomeuta species. Three types of olfactory sensilla could be distinguished, i.e. sensilla trichodea, sensilla basiconica, and sensilla coeloconica. Sexual dimorphism in the number of cells innervating sensilla trichodea could be established in 3 species. Most of these sensilla in males of Y. vigintipunctatus, Y. rorellus, and Y. cagnagellus are associated with 3 sensory cells, whereas in females of these species these sensilla contain 2 sensory cells. In both males and females of Y. padeltus and Y. malinellus, the great majority of the sensilla trichodea is innervated by 3 cells. So-called sensilla chaetica type 1 show features typical of a combined mechano/contact-chemoreceptor. No structures indicating a sensory function were found in sensilla chaetica type 11. Sensilla styloconica contain 3 cells, the dendritic outer segment of one being lamellated; most likely, these cells have a thermo- and hygroreceptive function. The findings concerning the olfactory sensilla are discussed in the context of olfactory communication and reproductive isolation in European Yponomeuta.     

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.     

Vergleichende Morphologie des Schmetterlingsrüssels und seiner Sensillen — Ein Beitrag zur phylogenetischen Systematik der Papilionoidea (Insecta, Lepidoptera)

Comparative morphology of the butterfly proboscis and its sensilla — a contribution to the phylogenetic systematics of Papilionoidea (Insecta, Lepidoptera) The morphology of the proboscis was investigated in more than 70 European representatives of Papilionoidea using light microscopy and scanning electron microscopy. The composition of the proboscis wall, its surface structures, as well as the shape and distribution of the different types of sensilla are compared. Special attention is given to the tip region and the diversity of the sensilla styloconica. Plesiomorphic features of the proboscis of Papilionoidea were found to include vertically extended exocuticular ribs composing the galeal wall, cuticular spines restricted to the ventral side of the proximal galea, and two rows of fluted sensilla styloconica restricted to the tip region. Apomorphic features of the proboscis in Papilionidae are three rows of small sensilla styloconica. The presence of cuticular spines all over the galeae was identified as an autapomorphy of Pieridae. Possible apomorphies of Nymphalidae are oblique exocuticular ribs of the galeal wall and the great number and length of the sensilla styloconica (significant at p < 0.01, t-test). A possible synapomorphy of Lycaenidae and Riodinidae are cuticlar spines up to the distal galeae. Distinct transformation series of sensilla styloconica give evidence that divergent evolutionary trends led from fluted shafts to a multitude of other shapes in Papilionidae, Nymphalidae (sensu lato), and Lycaenidae. Long smooth-shafted, club-shaped sensilla styloconica, bearing apical spines, are found in Nymphalinae, Apaturinae and Limenitidinae. Highly derived sensilla styloconica evolved in Heliconiinae and Melitaeini, which are arranged in only one row in both taxa. Their shafts are smooth, flattened and bear an excentral sensory cone. Further apomorphic character states are dented flutes which evolved several times, independently from each other in Satyrinae, Lycaeninae and Riodinidae. The results are discussed in a systematical context and provide the basis for a better understanding of the function of different morphological structures of the proboscis in feeding.     

Morphology and distribution of antennal sense organs and diversity of mouthpart structures in Odontopus nigricornis (Stall) and Nezara viridula L. (Hemiptera)

Sensilla on the antennae and labial tip of the adult hemipteran bugs, Odontopus nigricornis Stall (Pyrrhocoridae) and Nezara viridula L. (Pentatomidae) (Hemiptera) were examined with an electron microscope in order to study their morphology, distribution, and possible chemo- and mechanoreceptive functions for food detection. The antenna contains 2 types of sensilla trichodea and 3 types of sensilla basiconica on the flagellar segments. S. trichodea are most abundant in both insects. Long slender hairs with elevated bases, and slightly shorter hairs with flexible sockets at the bases are common in both species. However, on each antennal segment of O.nigricornis, 1 or 2 rows of very long trichodeal hairs with longitudinal grooves and blunt tips are visible. At the periphery, S. basiconica with bulbous bases were also observed in addition to sensilla chaetica. The tripartite apex of the labium in both species consists of 2 lateral lobes and an apical plate. Each lateral lobe possesses a field of 11 thick-walled uniporous peg sensilla and long non-porous hair sensilla. Mandibular stylets of O.nigricornis have barbs, which may help in penetrating the hard seed coat. These insects made circular holes while feeding on the seed. A possible mechanism of feeding is discussed.     

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.     

Expression of odorant-binding and chemosensory proteins and spatial map of chemosensilla on labial palps of Locusta migratoria (Orthoptera: Acrididae)

The sensilla on labial palps in Locusta migratoria were observed and mapped using light microscopy, scanning and transmission electron microscopy. A dome region on the tip of the fourth segment (distal segment) of labial palps is mainly covered with sensilla chaetica (about 98%), and few sensilla basiconica (2%). The total number of both types of sensilla is significantly higher in females than in males. Sensilla chaetica can be further subdivided into three groups containing 6, 7 or 10 neurons. Immunocytochemical localization of odorant-binding protein (OBP) and chemosensory proteins (CSPs) was performed on ultrathin sections of sensilla on labial palps. The antiserum against odorant-binding protein from Locusta migratoria (LmigOBP) only labelled sensilla basiconica, with gold granules only found in the sensillum lymph. Chemosensory protein instead was specifically present in the outer sensillum lymph of all three subgroups of sensilla chaetica with antiserum against CSP-I from Schistocerca gregaria (SgreCSP-I). In contrast these three subgroups were never labelled with antiserum against CSP-II from Locusta migratoria (LmigCSP-II). In addition, a few sensilla chaetica could not be stained with any of the antisera used.     

豆柄瘤蚜茧蜂触角感受器的扫描电镜观察(英文)

利用扫描电镜对豆柄瘤蚜茧蜂Lysiphlebus fabarum的触角感受器进行了观察, 发现有7 种感受器, 分别为毛形感受器、刺形感受器Ⅰ型、刺形感受器Ⅱ型、锥形感受器、腔锥形感受器Ⅰ型、腔锥形感受器Ⅱ型和板形感受器。毛形感受器是数量最多的感器; 除了腔锥形感受器Ⅱ型只在雌虫触角发现外, 雌、雄触角感受器的类型和结构没有较大的差别, 并且腔锥形感受器Ⅱ是数量最少的感器。