普通齿蛉幼虫的呼吸系统及呼吸行为

研究了普通齿蛉Neoneuromus ignobilis Navás幼虫的呼吸系统及其呼吸行为。结果表明:普通齿蛉幼虫为全气门式(10对气门)呼吸系统,前中胸、中后胸之间、腹部8节各有1对气门,腹部8节各有气管鳃1对,前6对细短,管状,有较短绒毛,后2对气管鳃较粗长,呈羽毛状。腹部1～7节各有1对毛簇,第8腹节无毛簇。侧纵干气管较粗,4束,自前胸前缘部分成左右2组,每组两根侧纵干气管,向胸腹部延伸,二级气管分别伸达各个气门和毛簇,腹部每节由毛簇处的二级气管分支而来的三级气管相连或延伸至消化道等处。气管鳃中无气管。有毛簇呼吸、气门呼吸和体壁呼吸3种呼吸方式,在水中以毛簇呼吸为主,在陆上进行气门呼吸和体壁呼吸。     

Trithorax: A new homoeotic mutation of Drosophila melanogaster causing transformations of abdominal and thoracic imaginal segments

Summary A new homoeotic mutation, trithorax ¹ (trx ¹), of Drosophila melanogaster is described which causes intersegmental transformations in both the adult thorax and abdomen. Specifically, the metathorax and ventral prothorax are partially transformed to mesothroax, whilst abdominal segments are partially transformed towards the first abdominal segment. Three variables are shown to influence the expressivity of the mutant phenotype: (1) presence of wild type copies of the gene in the female parent; (2) culture temperature during the first four hours of embryogenesis; (3) exposure of embryos to ether vapour at the blastoderm stage. In addition it is shown that phenocopies of the mutant phenotype can be induced by ether treatment of heterozygous trx ¹ embryos with a frequency higher than that of bithorax phenocopies in wild type embryos.These findings are together taken to imply that the mutated gene functions early during embryogenests, and that a common mechanism underlies the determination of all the thoracic and abdominal segments.     

Homeotic gene function in the muscles of Drosophila larvae

The segmental musculature of Drosophila melanogaster larvae consists of 24-30 muscles per segment. Unique patterns of muscles are found in the three thoracic segments and the first and last abdominal segments; the remaining abdominal segments share the same pattern. Mutations in Ultrabithorax (Ubx) cause partial transformation of the muscle pattern of larval abdominal segments towards metathorax. The muscles of the thorax are not affected. In the first two abdominal segments the changes include the loss of at least 11 `abdominal' muscles and the gain of 11 `thoracic' muscles. Less extensive transformations are seen in more posterior abdominal segments. Anterobithorax, bithorax, postbithorax and bithoraxoid mutations also induce transformations of the larval musculature. Each allelic group affects a domain that is a subset of the entire Ubx domain but these domains are not restricted to compartments or segments and may extend through as many as five segments. In the muscles the segmental distribution of Ubx antigen correlates with the segments affected by Ubx mutations. The different domains of Ubx in mesoderm and ectoderm argue that the segmental diversity of the muscle pattern is not simply induced by the overlying epidermis and that Ubx function in the mesoderm is required for the correct development of abdominal segments.     

Precursor structures and evolution of tympanal organs in Lepidoptera (Insecta, Pterygota)

 The patterns of scolopal organs and their innervation were studied by the methylene blue method in larvae, pupae and adults of an Yponomeuta species (Yponomeutidae) and of tympanate adult representatives of the Noctuoidea, Geometridae, Drepanidae and Pyraloidea. The studies were focused mainly on the mesothorax, the metathorax and some anterior abdominal segments. In the abdominal tympanal organs of Geometridae, Drepanidae and Pyraloidea, the auditory scolopidia are homologous with the lateral scolopal organs of the first abdominal segment; however, the hearing organs as such evolved independently in the three taxa. The studies confirm that the tympanal organ in the Noctuoidea is derived from the caudal dorsolateral region of the metathorax including its dorsal scolopal organ and the B-cell. The adult scolopal organs are present already in the larvae and are maintained nearly unchanged during metamorphosis to the adult. Only in the Noctuoidea are the three sensory cells of the larval scolopal organs, which become part of the tympanal organs, reduced to one (in Notodontidae) or two (in other Noctuoidea) during metamorphosis. A hypothetical scenario of the evolution of the tympanal organs is outlined. Accepted: 12 March 1997     

Compartments in the abdomen of Drosophila and the role of the engrailed locus

A clonal analysis has shown that the dorsal surface of the first abdominal segment of Drosophila melanogaster is subdivided into anterior and posterior compartments. Cells of the posterior compartment grow up to but not beyond the anterior-posterior compartment border within the first abdominal segment and the intersegmental border that defines the boundary between the first and second abdominal segments. Growing within these boundaries, a narrow band of tissue clonally isolated from the adjoining tissue is formed. When these posterior cells are deficient for the engrailed locus, however, neither the compartment nor the segment border is maintained. The implications, that compartmentalization is essential for segmentation, and that all insect segments are subdivided by anterior and posterior compartments, are discussed.     

<Emphasis Type="Italic">Pectapalochrus</Emphasis> gen. n., a new genus of soft-winged flower beetles of the tribe apalochrini (Coleoptera,Malachiidae)

Analysis of species of Dromanthomorphus Pic from South-East Asia has shown that the genus is distinguished by the following special male characters: flabellate, serrate, or filiform antennae; one-colored white pubescence of the surface; a swollen metathorax with a gladiate appendage; stout and excavate fore and middle tibiae; elongate and modified fore and middle coxae; apical tergites with a specific slanting and tile-like sculpture at the apex; apical abdominal sternites bilaciniate, with specifically sculptured apices. These characters are completely lacking in the Palaearctic species attributed to Dromanthomorphus, which are characterized by flabellate or serrate antennae, by a simple, not swollen metathorax lacking appendages, double white and black pubescence of the surface, simple, evenly rounded apical abdominal tergites, and evenly narrowed apical abdominal sternites emarginate in the middle and having simple, not sculptured apices. Based on these differences, a new genus, Pectapalochrus gen. n., is described for the Palaearctic species. Keys to Pectapalochrus species and to genera of Apalochrini of Eurasia and also illustrations of the habitus and male structures of the new genus are given.     

Before the wasp-waist: comparative anatomy and phylogenetic implications of the skeleto-musculature of the thoraco-abdominal boundary region in basal Hymenoptera (Insecta)

The skeleto-musculature of the metathorax and first abdominal segment was studied in representatives from all ’symphytan’ families. Forty-three informative characters were coded and scored. The distribution of character states are discussed with reference to recent cladistic treatments of the Hymenoptera. Previously unreported autapomorphies for the Hymenoptera are the separation of the metathoracic trochantins from the metepisterna and metacoxae, the position of the metafurca anteriorly on the discrimenal lamella of the metathorax and the presence of second abdominal sternum (S2)-metacoxal muscles. The absence of metapleuro-S2 muscles is an autapomorphy for the non-xyelid Hymenoptera. Putative autapomorphies of the Tenthredinoidea are: (1) the presence of transverse metanotal muscles, (2) the subdivision of the second phragmo-third phragmal muscles, part of which arises from the metalaterophragmal lobes, (3) the posterior thoracic spiracle occlusor muscles arising from the mesepisterna, (4) the absence of trochantins and metanoto-trochantinal muscles and (5) the presence of elongate lateral metafurcal arms. Having the paracoxal sulci extending along the anterior margins of the metepisterna and the anterior metafurcal arms reduced are synapomorphies for all tenthredinoid families excluding Blasticotomidae. The presence of transversely extended cenchri with hooks on their entire surface is a putative synapomorphy for Diprionidae + Cimbicidae + Argidae + Pergidae. The clade Cimbicidae + Argidae + Pergidae is supported by the absence of metanoto- metabasalar muscles, the fusion of the first abdominal tergite (T1) with the metepimera and the absence of posterior metapleuro-metafurcal muscles. Autapomorphies of the Cimbicidae are the absence of the metalaterophragmal lobes and the metalaterophragmal-metafurcal muscles. Having the mesoscutello-metanotal muscle inserting on a projection from the anterior margin of the metanotum, surrounding the tendon with sclerotised cuticle, is a synapomorphy for the Argidae and Pergidae. Autapomorphies of the Cephoidea are the absence of cenchri, the presence of distinct articulations between T1 and the metepimera, and having the paracoxal sulci extending subparallel with the metafurcal discrimen. The monophyly of the Siricidae is supported by the absence of the anapleural clefts and the presence of an elongate mesospina projecting posteriorly between the anterior metafurcal arms. The presence of a membranous pouch ventrally of T1 and of large T1-metafurcal muscles is unique to Xiphydria camelus among the taxa examined. The absence of hind wing tegulae, posterior metapleuro-metafurcal, metanoto-trochantinal and anterior metanoto-metacoxal muscles, and the presence of elongate lateral metafurcal arms are synapomorphies for Xiphydriidae + Orussidae + Apocrita. The Orussidae greatly resembles the Apocrita in the region studied, a synapomorphy for the two taxa being the presence of metepisternal depressions. An autapomorphy for the Apocrita is the fusion of T1 with the metapleural arms; these structures closely abut in Orussidae. The fusion of T1 with the metepimera was preceded by the reduction of the posterior parts of the metepimera, as observed in Anaxyelidae, Xiphydriidae, and Orussidae. This makes the lines of fusion between T1 and the metepimera confluent with the metapleural sulci in the Apocrita. There is no compelling evidence for considering the configuration of T1 and the metepimera in Cephoidea to be incipient in the formation of the propodeum in Apocrita. The close association between the meso- and metathorax and the integration of T1 in the metathorax evolved gradually twice within the basal hymenopteran lineages, culminating in the Apocrita and the Cimbicidae + Argidae + Pergidae clade. Accepted: 2 September 1999     

The probable significance of tracheal tufts in the 8th abdominal segment of Heliothis virescens (F.) on the development of its parasitoid, Toxoneuron nigriceps (Viereck)

The 8th abdominal segment of Heliothis virescens (Fabricius) larvae contains aerating trachea and tracheole tufts that end in the hemocoel of the 8th segment, unlike the tracheae that invade tissues in other segments. These tracheal tufts from the 8th abdominal segment extend to the tokus region, which along with the telson cavity is known to act as a “lung” for hemocytes in Calpodes ethlius and a few other lepidopteran larvae. The goal of this research was to study the effects of these tracheal tufts in the 8th abdominal segment on parasitoid development inside the host larvae, H. virescens. The first objective was to determine if the eggs of the parasitoid, Toxoneuron nigriceps, are predominantly located among the tracheal tufts of the 8th abdominal segment compared to other body cavity regions irrespective of their oviposition site or the position of the host larvae. The results showed that several hours after oviposition most of the eggs are found in the 8th abdominal segment irrespective of the oviposition site or the position of the host larvae. The second objective was to study the effect of varying oxygen concentrations in vitro on various developmental stages of the egg. The results showed that decreasing oxygen concentrations adversely affects the parasitoid egg development in vitro. A third objective was to determine the oxygen concentration in 8th abdominal segment of the host larvae and compare it to other regions of the body using an oxygen sensor placed in vivo. The results suggested relatively high concentration of oxygen in the 8th abdominal segment compared to other regions of the host, thus supporting our hypothesis that the increased oxygen level in the 8th abdominal segment is important to the development of the parasitoid eggs.     

RT-qPCR based quantitative analysis of gene expression in single bacterial cells

Recent evidence suggests that cell-to-cell difference at the gene expression level is an order of magnitude greater than previously thought even for isogenic bacterial populations. Such gene expression heterogeneity determines the fate of individual bacterial cells in populations and could also affect the ultimate fate of populations themselves. To quantify the heterogeneity and its biological significance, quantitative methods to measure gene expression in single bacterial cells are needed. In this work, we developed two SYBR Green-based RT-qPCR methods to determine gene expression directly in single bacterial cells. The first method involves a single-tube operation that can analyze one gene from each bacterial cell. The second method is featured by a two-stage protocol that consists of RNA isolation from a single bacterial cell and cDNA synthesis in the first stage, and qPCR in the second stage, which allows determination of expression level of multiple genes simultaneously for single bacterial cells of both gram-positive and negative. We applied the methods to stress-treated (i.e. low pH and high temperature) Escherichia coli populations. The reproducible results demonstrated that the method is sensitive enough not only for measuring cellular responses at the single-cell level, but also for revealing gene expression heterogeneity among the bacterial cells. Furthermore, our results showed that the two-stage method can reproducibly measure multiple highly expressed genes from a single E. coli cell, which exhibits important foundation for future development of a high throughput and lab-on-chips whole-genome RT-qPCR methodology for single bacterial cells.     

A clonal analysis of tergite development in Drosophila of ultraabdominal and paradoxical genotypes.

The developmental parameters of homeotic second abdominal anlage cells in flies with Ultraabdominal and paradoxical genotypes are compared with those of normal second abdominal anlage cells through the use of induced mitotic recombination to mark the clonal descendants of single anlage cells. Homeotic and normal second abdominal anlage cells show the same pattern of mitotic activity during development. The homeotic second abdominal anlage cells with Ultraabdominal genotype proliferate to the same extent as normal anlage cells during hemitergite formation. However, the proliferation of homeotic second abdominal anlage cells with paradoxical genotype is decreased due to the failure of some daughter cells either to divide or to differentiate normally. The number of anlage cells in a homeotic second abdominal histoblast with Ultraabdominal genotype is slightly smaller and more variable than that in a normal second abdominal histoblast. The number of anlage cells in a homeotic second abdominal histoblast with paradoxical genotype is much smaller and much more variable than that in a normal second abdominal histoblast. These results are discussed in relation to mechanisms governing cell determination. In addition, some aspects of pattern formation in incomplete homeotic second abdominal hemitergites are presented and discussed.     

Paratullbergia Womersley in China: the description of a new species and a key to the genus (Collembola,Tullbergiidae)

The genus Paratullbergia Womersley, 1930 is recorded for the first time from China. Paratullbergia changfengensis sp. n. from Shanghai is described and illustrated. It is characterized by the presence of 1+1 pseudocelli on thoracic segment I, with two pairs of pseudocelli on each of thoracic segments II and III, presence of seta px on abdominal segment IV, seta a2 and p4 on abdominal segment V as microsetae, and less differentiated sensory seta p3 on abdominal segment V. Both sexes present. The new species can be easily distinguished from its congeners by the presence of pseudocelli on thoracic segment I. An updated key to the world species of the genus Paratullbergia is provided.     

斜脉蝠蛾幼虫分类特征研究

本文研究报道了冬虫夏草主要寄主之一斜脉蝠蛾Hipialus oblifurcus Chu et Wang幼虫头、胸、腹各部分的形态特征、颜色、毛序及各龄幼虫的头宽和体长,可作为鉴别种类的依据。     

Harmonic analysis of Boolean networks: determinative power and perturbations

Consider a large Boolean network with a feed forward structure. Given a probability distribution on the inputs, can one find, possibly small, collections of input nodes that determine the states of most other nodes in the network? To answer this question, a notion that quantifies the determinative power of an input over the states of the nodes in the network is needed. We argue that the mutual information (MI) between a given subset of the inputs X={X₁,...,X_n} of some node i and its associated function f_i(X) quantifies the determinative power of this set of inputs over node i. We compare the determinative power of a set of inputs to the sensitivity to perturbations to these inputs, and find that, maybe surprisingly, an input that has large sensitivity to perturbations does not necessarily have large determinative power. However, for unate functions, which play an important role in genetic regulatory networks, we find a direct relation between MI and sensitivity to perturbations. As an application of our results, we analyze the large-scale regulatory network of Escherichia coli. We identify the most determinative nodes and show that a small subset of those reduces the overall uncertainty of the network state significantly. Furthermore, the network is found to be tolerant to perturbations of its inputs.     

Morphology and Volatile Compounds of Metathoracic Scent Gland in Tessaratoma papillosa (Drury) (Hemiptera: Tessaratomidae)

Tessaratoma papillosa (Drury) (Hemiptera: Tessaratomidae) is a serious insect pest of litchi and longan in South China. When disturbed, this insect could release large quantities of disagreeable odorous volatiles from its scent gland. Knowledge on the scent gland and its secretion is crucial for developing the semiochemical methods to manage this pest. Morphology and ultrastructure of the metathoracic scent glands (MTGs) were studied under stereo and scanning electron microscopy, and the volatile compounds of MTGs from both male and female T. papillosa were analyzed with coupled gas chromatography?Cmass spectrometry (GC?CMS). The MTG complex is located between the metathorax and the first abdominal segment at the ventral surface of the insect, which has a well-developed single double valve cystic-shaped orange median reservoir, paired colorless lateral glands in both sides, and a long and wavy tubular accessory gland that inlays tightly into the ventral edge around the median reservoir. The MTG opens to the body surface through paired ostioles located between the meso- and metacoxae of the evaporatorium with mushroom bodies. The GC?CMS analyses showed that female and male adults have nine major volatile components in common. Tridecane is the most abundant in both females and males, reaching up to 47.1% and 51.8% of relative amount, respectively. The minor component is benzophenone with only 0.28% and 0.14%. Furthermore, undecane, tetradecane, 3-methyl-tridecane, and cyclopentadecane were found only in males. The possible function of volatile compounds of MTG contents in T. papillosa is addressed.     

Analysis of larval segmentation in lethal genotypes associated with the antennapedia gene complex in Drosophila melanogaster

The segment pattern of larval cuticular structures was examined for individuals bearing lethal genotypes associated with the Antennapedia gene complex (ANT-C). The results provide new evidence for the role of this complex in body segmentation in Drosophila and demonstrate that the ANT-C, like the bithorax complex, effects both larval and imaginal tissues. Lethal genotypes involving new EMS induced lesions or dominant homoeotic mutations (Antp or Antp^Scx) of the Antennapedia complementation group show anomalies in the larval meso- and metathorax. The phenotype is interpreted as a homoeotic transformation of the meso- and metathorax to prothorax. We suggest that Antp⁺ functions in the elicitation of mesothoracic development above that of a prothoracic level in the ventral meso- and metathorax. The lethality of the Sex combs reduced complementation group, which includes the mutation Multiple sex combs (Msc), is characterized by incomplete head formation and the lack of definitive prothoracic ventral setal belts. These results indicate that Scr⁺ is necessary for normal development of the prothorax and are consistent with earlier interpretations based on adult phenotypes. Five other lethal complementation sites, assigned to polytene chromosome interval 84A-B1,2 have been analyzed. They are not associated with dominant homoeotic phenotypes in the adult. The terminal phenotype of individuals carrying lethal mutations in the W36, R11, or R14 complementation groups demonstrate that these loci are important in normal anterior development and/or body segmentation and suggest functional relationships to the homoeotic mutations previously localized to the 84A-84B1,2 polytene interval.     

福腮钩土蜂生物学及其利用的研究

福腮钩土蜂是大黑鳃金龟幼虫的一种外寄生天敌。成蜂以红麻、甘薯蜜腺和菜豆花蜜为补充营养,卵主要产于寄主后胸与第一腹节之间的腹面．单雌平均产卵22粒。幼虫共4龄,咀食寄主组织,只残留头壳,老熟幼虫作茧越冬。生活史有1年1代和2年1代型,成蜂发生时期与大黑鳃金龟发生期相一致。据此提出,在花生田种植蜜源植物,为土蜂提供食物资源．通过从蜂源地助迁土蜂已在邹城市定居．展示有明显的自然控制作用。     

The morphology of larvae and systematics of the leaf-beetles Chrysolina tundralis and Chrysolina roddi (Coleoptera, Chrysomelidae, Chrysomelinae)

The 1st- and 4th-instar larvae of Chrysolina tundralis and Ch. roddi and the egg of the latter species are described for the first time; the instar-related changes of the larval morphology are discussed. The 4th-instar larva of Ch. tundralis is very similar to that of Ch. septentrionalis, but differs in the smaller sclerite-like plates of the abdominal segments and wider spaces between them (4–7 times as wide as a sclerite-like plate). The 4th-instar larva of Ch. roddi is very similar to that of Ch. pedestris, but differs in the dark brown coloration of the body and a fewer number of setae (9–12) in the dorsolateral areas of the meso- and metathorax. Data on the habitats and host plants of the larvae are given.     

Developmental analysis of some mutants of the bithorax system ofDrosophila

Summary Mutants in the bithorax system ofDrosophila produce homeotic transformations that affect the mesothoracic, metathoracic and first abdominal segments. In the present report we describe a clonal analysis of the development of those mutants transforming the metathorax and first abdominal segments into mesothorax.The main results indicate that (1) The normal dorsal metathoracic (haltere) disk has similar developmental parameters to the dorsal mesothoracic disk. The main difference is that the initial and final numbers of cells are different in both disks. (2) In flies mutant forBithorax andpostbithorax (which transform the haltere into wing) the transformed haltere disk has the same initial and final number of cells as the normal wing disk. (3) In morphogenetic mosaics homozygousbithorax (andpostbithorax) clones express their genotype autonomously regardless of the genotype of surrounding haltere cells. This autonomy is expressed in a regulation of the number of adult cells per compartment, typical cell affinities and final cuticular differentiation.