雷氏黄萤幼虫呼吸系统和呼吸行为

研究雷氏黄萤Luciola leii Fu and Ballantyne幼虫的呼吸系统及其呼吸行为。结果表明:雷氏黄萤幼虫的呼吸系统中只有气管无气囊。前胸、中胸和后胸均分布有气门,无气管鳃,腹部1~8节分布有气门和气管鳃,气门腔基部和气管鳃基部相连,呈"√"状,气管鳃内气管与气门气管相连通。雷氏黄萤幼虫的呼吸行为分为3种:利用胸部气门呼吸、腹部气门呼吸和气管鳃呼吸,其中以腹部气门呼吸为主。     

Comparative micromorphology of third instar larvae and the breeding biology of some Afrotropical Sarcophaga (Diptera: Sarcophagidae)

Four sympatric species of Sarcophaga, viz S. cruentata Meigen, S. exuberans Pandelle, S. nodosa Engel and S. tibialis Macquart, which occur in the Transvaal, South Africa, showed oviparity under optimum laboratory breeding conditions. Details of the life cycle duration under these conditions are discussed. Rearing and colonizing methods were developed. Scanning electron microscopy of third instar larvae provided useful data in distinguishing between the four species. The characters which were examined were the spinulation of the body segments and the rim surrounding the spiracular atrium of the posterior spiracles, the anterior spiracles and the spiracular hairs of the posterior spiracles.     

Scanning electron microscopy of Oestrus ovis larvae (Diptera: Oestridae): skin armour and posterior spiracles

The skin armour and posterior spiracles of L1, L2 and L3 of Oestrus ovis (Diptera: Oestridae) are described and documented photographically by a scanning electron microscope. The complex and variable morphology of the attack organs of larvae of different stages makes it easier to understand better their exceeding adaptability to the host. The SEM survey has also allowed an apparently unreported anatomic particular with a probable sensory function to be detected in L1.     

Observations on Aepophilus bonnairei (Signoret) (Saldidae: Hemiptera) an intertidal insect of rocky shores

Morphological adaptations of the littoral hemipteran Aepophilus bonnairei Sign, to its environment are examined. Particular emphasis is paid to the distribution of the plastron formed by microtrichia and structures around the thoracic spiracles.     

Morphology of the first instar of Calliphora vicina, Phormia regina and Lucilia illustris (Diptera, Calliphoridae)

Scanning electron microscopy documentation of first instar Calliphora vicina Robineau-Desvoidy, Phormia regina (Meigen) and Lucilia illustris (Meigen) (Diptera: Calliphoridae) is presented for the first time, and the following morphological structures are documented: pseudocephalon; antenna; maxillary palpus; facial mask; labial lobe; thoracic and abdominal spinulation; spiracular field; posterior spiracles, and anal pad. Light microscopy documentation and illustrations are provided for the cephaloskeleton in lateral and ventral views. New diagnostic features are revealed in the configuration of the facial mask, cephaloskeleton and posterior spiracles. The first instar morphology of C. vicina, Ph. regina and L. illustris is discussed in the light of existing knowledge about early instars of blowflies.     

Morphology and ultrastructure of spiracles in phlebotomine sandfly larvae

The morphology and ultrastructure of the larval spiracle system of three phlebotomine sandfly species, Phlebotomus perniciosus, P. perfiliewi and P. papatasi, were examined by scanning (SEM) and transmission (TEM) electron microscopy and by confocal scanning laser microscopy (CSLM). During larval development, thoracic and abdominal spiracles show considerable modifications. In fourth instar larvae, the spiracles consist of a plate with a sclerotized central portion and a peripheral circle of papillae. The latter is distinctive in the larvae of P. papatasi, which are readily distinguished from the other species. Opening clefts across the papillae communicate with an internal chamber that encircles an electrondense plug. Many cylindrical projections cross the chamber, uniting the central plug with the larval body, forming an air filter. Spiracular development in successive larval instars has both a taxonomic and adaptive value.     

The role of the spiracles in gas exchange during development of Samia cynthia (Lepidoptera, Saturniidae).

Spiracles and the tracheal system of insects allow effective delivery of respiratory gases. During development, holometabolous insects encounter large changes in the functional morphology of gas exchange structures. To investigate changes in respiratory patterns during development, CO2-release was measured in larvae, pre-pupae and pupae of Samia cynthia (Lepidoptera, Saturniidae). Gas exchange patterns showed great variability. Caterpillars had high metabolic rates and released carbon dioxide continuously. Pre-pupae and pupae showed typical discontinuous gas exchange cycles (DGC) at reduced metabolic rates. Changes in gas exchange patterns can partly be explained with low metabolic rates during pupation. Sequential blocking of spiracles in pre-pupae and pupae reduced spiracle conductance with tracheal conductance remaining unaffected. Analysis of gas exchange patterns indicates that caterpillars and pre-pupae use more than 14 spiracles simultaneously while pupae only use 8 to 10 spiracles. Total conductance is not a simple multiple of single spiracles, but may be gradually adaptable to gas exchange demands. Surprisingly, moth pupae showed a DGC if all except one spiracle were blocked. The huge conductance of single spiracles is discussed as a pre-adaptation to high metabolic demands at the beginning and the end of the pupal as well as in the adult stage.     

The structure and behaviour of Notiphila riparia and Erioptera squalida, two root-piercing insects

Two species of root-piercing insect, Notiphila riparia (Ephydridae) and Erioptera squalida (Tipulidae) are described. The insertion of the spiracles into the plants is dependent on a firm environment which provides the main bracing element for the movements of the spiracles. The structural features of root-piercing spiracles are described. The spiracles are long enough to reach the gas spaces of the roots of the plants on which the insects are commonly found. The plant epidermis may act as a limiting factor in the respiration of the insects. The emergence of the adults of Erioptera squalida involves a change in buoyancy in the pharate adult as the adult emerges at the surface.     

Morphological aspects of the third instar larva of Haematobia irritans

The main morphological features of the cephalic region of the larva of Haematobia irritans (L.) are the oral grooves, tripartite labium and the antennomaxillary protuberances that have the dorsal, terminal and ventral sensory organs. The total number of sensilla that are found on the terminal organ differs from other cyclorrhaphous-fly larvae. The fan-shaped anterior spiracles usually consist of seven bulbous digits that are unequal in length. The creeping welts consist of notched, convex plates that split into two separate plates as they approach the midline of the venter. This characteristic has not been described previously for this species or other, higher, dipterous larvae. There are two posterior spiracles with an ecdysial scar, four fan-shaped and branching spiracular hairs and irregularly-shaped spiracular openings. The longitudinal anal opening is situated in the cuticular band that is known as the anal organ.     

Distinction among the puparia of three blowfly species (Diptera: Calliphoridae) frequently found on unburied corpses

Calliphorid larvae are important in the decomposition of carrion. Since these larvae are present in the primary stages of succession on carcasses, they may be important indicators of death time and the movement of corpses in homicide investigations. In this study we examined the morphological differences among puparia of Chrysomya megacephala, C. putoria and Cochliomyia macellaria. Puparia of the three species (N=30, each) were obtained from the F2 generation bred in culture medium at 25 degrees C, and 60% relative humidity on a 12 h photoperiod. The interspecific differences found were related to the conspicuousness of six tubercles located in the region near the posterior spiracles and to the distance between the two peritrema involving the spiracles. The latter were (mean +/- SD) 15.2 +/- 3.1 microm for C. megacephala, 18.8 +/- 2.8 microm for C. putoria and 16.5 +/- 3.5 microm for C. macellaria. The results of the present study may be useful in forensic entomology.     

Expression and function of the empty spiracles gene in olfactory sense organ development of Drosophila melanogaster

In Drosophila, the cephalic gap gene empty spiracles plays key roles in embryonic patterning of the peripheral and central nervous system. During postembryonic development, it is involved in the development of central olfactory circuitry in the antennal lobe of the adult. However, its possible role in the postembryonic development of peripheral olfactory sense organs has not been investigated. Here, we show that empty spiracles acts in a subset of precursors that generate the olfactory sense organs of the adult antenna. All empty spiracles-expressing precursor cells co-express the proneural gene amos and the early patterning gene lozenge. Moreover, the expression of empty spiracles in these precursor cells is dependent on both amos and lozenge. Functional analysis reveals two distinct roles of empty spiracles in the development of olfactory sense organs. Genetic interaction studies in a lozenge-sensitized background uncover a requirement of empty spiracles in the formation of trichoid and basiconic olfactory sensilla. MARCM-based clonal mutant analysis reveals an additional role during axonal targeting of olfactory sensory neurons to glomeruli within the antennal lobe. Our findings on empty spiracles action in olfactory sense organ development complement previous studies that demonstrate its requirement in olfactory interneurons and, taken together with studies on the murine homologs of empty spiracles, suggest that conserved molecular genetic programs might be responsible for the formation of both peripheral and central olfactory circuitry in insects and mammals.     

Respiratory significance of the thoracic and abdominal morphology of Belostoma and Ranatra (insecta,heteroptera)

Summary Both Belostoma and Ranatra possess I–II, subepimeral, thoracic subalar, and abdominal subalar air stores. In Belostoma, unlike Ranatra, the subepimeral air store is greatly enlarged, the abdominal subalar store is partially exposed to the water, and a fully exposed ventral abdominal air store is also present. All the air stores of Ranatra are normally concealed.The mesothoracic and metathoracic spiracles, which open onto the I–II and subepimeral air stores respectively, are of limited permeability. They appear to have less respiratory importance than the large and highly permeable first abdominal spiracles, which lie in the subalar air space and can probably exhale and inhale large amounts of air. The large eighth abdominal spiracles, which lie at the base of the siphon or retractile organ, can also inhale or exhale much air in Ranatra but appear to be mainly exhalant in Belostoma. The smaller second through seventh abdominal spiracles structurally resemble the eighth ones in Belostoma and open onto the ventral abdominal air store. In Ranatra they appear to have no significant respiratory function.Both genera obtain atmospheric air and give off exhaled air by means of the posterior retractile organ or siphon. The two types of air appear to follow different pathways in the two genera. In Ranatra atmospheric air appears to enter the tracheal system mainly or entirely through the eighth abdominal spiracles and then passes through the first abdominal spiracles into the subalar space. Exhaled air follows the reverse pathway. In Belostoma, however, atmospheric air probably enters the tracheae mainly through the first abdominal spiracles; it is conveyed to these spiracles from the retractile organ through the subalar space or, more indirectly, through the ventral abdominal air store. Air exhaled through the first abdominal spiracles follows the reverse route; the eighth abdominal spiracles can also exhale directly into the base of the retractile organ.During underwater respiration the abdominal portion of the subalar air store appears to be the main reservoir for oxygen. The subalar oxygen is initially atmospheric, and is supplemented, during submersion, by other sources of oxygen. Belostoma may use its exposed ventral abdominal air store, and its partially exposed abdominal subalar one, as physical gills; both these stores communicate with the inhalant first abdominal spiracles. Ranatra, none of whose air stores are normally exposed, appears, to be less capable of utilizing dissolved oxygen, but the considerable amount of atmospheric oxygen in the elongated siphon may be inhaled, during submersion, through the eighth abdominal spiracles.In both genera the thoracic air stores appear to be of less respiratory importance than the abdominal ones. They do not appear capable of obtaining large amounts of oxygen, and the thoracic spiracles are relatively impermeable. All the air stores, however, serve to protect the spiracles against the entry of water, and also contribute to the body's hydrostatic balance. It is also possible that some of the air stores play a role in pressure reception.The literature indicates much intergeneric variation in the respiration of Belostomatidae and Nepidae. In the Belostomatidae there is considerable variation in the extent of the ventral abdominal air store and in the roles of the subalar air store and the spiracles. The Nepidae show differences in their ability to utilize dissolved oxygen and in the extent of the subepimeral air store.     

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。     

The role of the spiracles in gas exchange during development of Samia cynthia (Lepidoptera, Saturniidae)

Spiracles and the tracheal system of insects allow effective delivery of respiratory gases. During development, holometabolous insects encounter large changes in the functional morphology of gas exchange structures. To investigate changes in respiratory patterns during development, CO₂-release was measured in larvae, pre-pupae and pupae of Samia cynthia (Lepidoptera, Saturniidae). Gas exchange patterns showed great variability. Caterpillars had high metabolic rates and released carbon dioxide continuously. Pre-pupae and pupae showed typical discontinuous gas exchange cycles (DGC) at reduced metabolic rates. Changes in gas exchange patterns can partly be explained with low metabolic rates during pupation. Sequential blocking of spiracles in pre-pupae and pupae reduced spiracle conductance with tracheal conductance remaining unaffected. Analysis of gas exchange patterns indicates that caterpillars and pre-pupae use more than 14 spiracles simultaneously while pupae only use 8 to 10 spiracles. Total conductance is not a simple multiple of single spiracles, but may be gradually adaptable to gas exchange demands. Surprisingly, moth pupae showed a DGC if all except one spiracle were blocked. The huge conductance of single spiracles is discussed as a pre-adaptation to high metabolic demands at the beginning and the end of the pupal as well as in the adult stage.     

Neural control of homologous behaviour patterns in two blaberid cockroaches

Activity patterns of motoneurones which innervate spiracular muscles in two blaberid cockroaches, Blaberus discoidalis and Gromphadorhina portentosa, have been monitored during two homologous behaviour patterns: respiratory and non-respiratory tracheal ventilation. Based upon the activity of spiracular motoneurones during these two activities, the abdominal spiracles have been divided into three functional groups: vestigial, respiratory and non-respiratory. In Blaberus discoidalis spiracle 3 is vestigial, spiracles 6, 7, 8 and 10 are respiratory, and spiracles 4, 5 and 9 are non-respiratory. In Gromphadorhina portentosa spiracles 3 and 10 are vestigial, spiracle 4 is non-respiratory and spiracles 5–9 are respiratory.Respiratory spiracles in both species are characterized by activity patterns of their motoneurones during respiratory tracheal ventilation: low frequency firing at irregular intervals during the respiratory pause and a higher frequency burst synchronous with the expiratory abdominal compression. Non-respiratory spiracles are characterized by complete inactivity of their opener motoneurones during respiratory tracheal ventilation. These motoneurones are activated by mechanical stimulation in both species, which simultaneously suppresses activity in respiratory opener motoneurones. In Blaberus discoidalis, there are no differences between activity patterns of respiratory and non-respiratory closer motoneurones. In Gromphadorhina portentosa, not only do respiratory and non-respiratory closer motoneurones have different activity patterns, but the activity pattern of respiratory closer motoneurones is different during respiratory and non-respiratory tracheal ventilation. The functional implications of these several spiracular motoneurone activity patterns are discussed.     

On the biology of the bird parasite <Emphasis Type="Italic">Neottiophilum praeustum</Emphasis> (Meigen, 1826) (Diptera,Neottiophilidae)

The first data on blood-sucking ectoparasitic larvae of Neottiophilum praeustum (Meig.) which develop in bird nests are presented in Russia, with the fieldfare Turdus pilaris L. as a host example. Larval development takes not more than 10–12 days but no puparia are formed until late autumn. The larvae of Neottiophilum resemble those of calliphorid flies both in body structure and life mode. The main diagnostic characters of Neottiophilum larvae distinguishing them from calliphorid ones are the spiracular disk of the posterior spiracles being positioned dorsal rather than ventral to the stigmal plate and lying outside rather than inside its peritreme. In addition, the anterior spiracles have 14–15, rather than 3–8 spiracular chambers.     

Spiracle activity in moth pupae—The role of oxygen and carbon dioxide revisited

After decades of intensive research, the actual mechanism behind discontinuous gas exchange in insects has not been fully understood. One open question concerns the actual way (closed, flutter, and open) of how spiracles respond to tracheal gas concentrations. As the results of a classic paper [Burkett, B.N., Schneiderman, H.A., 1974. Roles of oxygen and carbon dioxide in the control of spiracular function in cecropia pupae. Biological Bulletin 147, 274-293] allow ambiguous interpretation, we thus reexamined the behavior of the spiracles in response to fixed, controlled endotracheal gas concentrations.The tracheal system of diapausing pupae of Attacus atlas (Saturniidae, Lepidoptera) was flushed with gas mixtures varying in PO₂ and PCO₂ while the behavior of the spiracles was monitored using changes in the pressure signal. This novel pressure based technique proved to be superior to classic visual observation of single spiracles. A two-dimensional map of the spiracle behavior in response to endotracheal PO₂ and PCO₂ was established. Typically, it contained two distinct regions only, corresponding to “closed” and “open” spiracles. A separate “flutter” region was missing. Because fluttering is commonly observed in moth pupae, we suggest that the intermittent spiracle opening during a flutter phase is an effect of non-steady-state conditions within the tracheal system. For low PCO₂ the minimum PO₂ resulting in open spiracles was linearly dependent upon PCO₂. Above a threshold of 1-1.5 kPa CO₂ the spiracles were open irrespective of PO₂. We propose a hypothetical spiracular control model, which is simple and explains the time course of endotracheal partial pressures during all phases of discontinuous gas exchange.     

Effects of temperature and humidity on transpiration in adults of the lesser mealworm,Alphitobius diaperinus (Coleoptera: Tenebrionidae)

Measurements of water loss were made on adults of the lesser mealworm, Alphitobius diaperinus, using a recording micro-electrobalance and a programmable heat circulator bath. This species originates in tropical regions and infests poultry houses in temperate countries. Two routes of water loss were examined: the general cuticle and via the spiracles. Temperature and relative humidity of the ambient air substantially affect the cuticular transpiration in adults (fresh body weights from 12 mg to 22 mg). At near 0% R.H., between 20 and 40 degrees C the rate of body water loss gradually increased; on the other hand, the insects gained weight in an atmosphere close to saturation. Above 40 degrees C transpiration flow abruptly increased coinciding with the start of vigorous locomotor activity. This critical point corresponds to the opening of the spiracles from which the water is expelled from the tracheal system.In dead specimens, killed by cyanide or solvent, the water vapour slowly diffused out of the spiracles and, as in atracheate insects, the transpiration curves did not show a peak as the air temperature was increased.The thermostupor point (TSP) occurred as the insects became motionless; the corresponding temperature is significantly affected by atmospheric relative humidity (TSP=47.4+/-0.6 degrees C at c. 0% R.H.; TSP=46.6+/-0.7 degrees C at c. 100% R.H.).The transpiration flow was about four times as fast in specimens treated with solvent as in the individuals (live or cyanide-killed) that had undamaged water-proof cuticle. This species has to cope with a double challenge: (i) to adapt its physiology and ecology to poultry-house conditions which constitutes an extension of its primary habitats, and (ii) to survive over winter; high drought resistance and heat tolerance may constitute a pre-adaptation to conquer anthropogenic air-conditioned sites.     

Scanning electron microscopy of the posterior spiracles of cattle grubs Hypoderma bovis and Hypoderma lineatum

Posterior spiracles of newly hatched first instar larvae of Hypoderma bovis (L.) and H. lineatum (DeVill.) consist of two pairs of spiracular openings. Each pair is surrounded by a rima bearing three spines. Posterior spiracles of second instar larvae are composed of a pair of medial ecdysial scars bounded laterally by spiracular plates. H. bovis spiracular plates have twenty-nine to forty openings, each surrounded by a slightly raised rima. H. lineatum spiracular plates have eighteen to twenty-five openings. Spiracular openings lead to posterior felt chambers which are connected to a common anterior felt chamber filled with a meshlike network. In third instar H. bovis each medial ecdysial scar is surrounded by a strongly concave spiracular plate. Spiracular openings are surrounded by slightly raised rima. Most rimae bear a spine. Spiracular plates of H. lineatum are flat and rimae are without spines. Each spiracular opening leads to a posterior felt chamber, several of which are confluent with a larger anterior felt chamber. Anterior felt chambers open into the dorsal longitudinal tracheal trunk. Felt chambers in third instar larvae are also filled with a complex mesh.