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Kabkaew L. Sukontason - One of the best experts on this subject based on the ideXlab platform.
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morphology of immature stages of flesh flies boettcherisca nathani and lioproctia pattoni diptera sarcophagidae
Acta Tropica, 2016Co-Authors: Chutharat Samerjai, Kom Sukontason, Sangob Sanit, Nimit Morakote, Anchalee Wannasan, Roberto M Pereira, Kabkaew L. SukontasonAbstract:Abstract The flesh flies are medically-important because the larvae found in the human corpses can provide evidence in forensic investigations through larva identification and their developmental rate. Firstly, we thoroughly described the larval morphology of Boettcherisca nathani and Lioproctia pattoni, using scanning electron microscopy (SEM). The third instar of the two species differed markedly in two characters: (1) spines between the prothorax and mesothorax−B. nathani has more or less slender triangular spines, with those at the posterior region more slender than the anterior region; whereas L. pattoni has stout triangular spines with one or two tips anteriorly, with smaller and tapered triangular shape, grouped two to four laterally in the posterior end, and (2) morphology of the peristigmatic tufts at the posterior Spiracle−B. nathani has extensively branched long, fine hairs, whereas tufts in L. pattoni have moderately branched long, fine hairs. The anterior Spiracle displayed similarity; B. nathani has two irregular rows of 21–27 papillae, while L. pattoni has a single irregular row of 20–28 papillae. Secondly, we use light microscopy to compare morphology of the third instar of the two species and additional three species, i.e., Bercaea africa, Parasarcophaga dux and Liopygia ruficornis. Particular attention was paid to the features of anterior Spiracle, spines between prothorax and mesothorax and posterior Spiracle. These results are useful in species identification and estimation of age of larvae found associated with corpses.
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Morphological descriptions for the identification of Hypopygiopsis tumrasvini Kurahashi (Diptera: Calliphoridae)
Parasitology Research, 2011Co-Authors: Kittikhun Moophayak, Roy C. Vogtsberger, Kom Sukontason, Kabkaew L. SukontasonAbstract:This article presents morphological descriptions of larvae and adults of Hypopygiopsis tumrasvini Kurahashi (Diptera: Calliphoridae), a blow fly species that may be of forensic importance. Both second and third instar larvae are illustrated, with emphasis placed on important characteristic features used for larval identification, such as the cephalopharyngeal skeleton, anterior and posterior Spiracles, and dorsal spines between the prothorax and mesothorax. Eight to 11 papillae were found on each anterior Spiracle arranged in a single row. The dorsal spines between the prothorax and mesothorax were arranged in sets of posteriorly projecting acuminate spines with darkly pigmented tips. The posterior Spiracles each bear three prominent and separated long, slender spiracular slits encircled by a dark, thick peritreme that is complete ventromedially around a button. Prominent inner projection of peritreme is seen between the middle and lower spiracular slits. A previously published key for differentiating third instar larvae of flies of possible forensic importance in Thailand is updated to include this additional species. Some characteristic features of males and females of the species are also provided.
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Ultrastructure of Spiracles of Musca domestica and Hydrotaea chalcogaster (Diptera: Muscidae)
Parasitology Research, 2006Co-Authors: Rungkanta Methanitikorn, Worachote Boonsriwong, Somsak Piangjai, Hiromu Kurahashi, Roy C. Vogtsberger, Kabkaew L. SukontasonAbstract:Spiracles are major respiratory openings in the exoskeleton of insects. Oxygen, a necessary gas for cell activity, must pass through the Spiracle to enter the respiratory system. In this study, we investigated the fine structure of Spiracles of adult females of Musca domestica L. and Hydrotaea chalcogaster (Wiedemann), both medically important fly species in many parts of the world, by utilizing scanning electron microscopy. The mesothoracic Spiracle of M. domestica is large and elongate-oval in shape, with its anterior end being gradually tapered. The outer surface is densely covered with slender setae of variable distribution and orientation. The metathoracic Spiracle is semicircular or D-shaped, with its rim possessing long, fine, inwardly curved setae. A net-like valve or sieve plate, which has a smooth rim with swollen surface, is located within the atrium of this species. The abdominal Spiracles are circular with a symmetrically swollen peritreme surrounding the opening. The inner filtering apparatus is composed of many spiral tubes, each possessing many small spines. As for H. chalcogaster , the tapering mesothoracic Spiracle is covered with long setae arranged consistently inward from the peritreme, giving it a “combed” appearance. The metathoracic Spiracle is similarly arranged but triangularly rounded in shape, with the anterior and posterior rims possessing long fine setae. The net-like valve within the atrium has a smooth, swollen rim, whereas the inner edge of the atrium bears short, slender setae where it meets with the peritreme of the Spiracle. The abdominal Spiracles of this species look similar to that of M. domestica , with the exception of the filtering apparatus that bears only a few small spines. The function of these Spiracles is discussed.
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differentiation of the third instar of forensically important fly species in thailand
Annals of The Entomological Society of America, 2004Co-Authors: Kabkaew L. Sukontason, Kom Sukontason, Radchadawan Ngernklun, Duanghatai Sripakdee, Somsak PiangjaiAbstract:Differentiation of the third instar of forensically important fly species in Thailand was performed using light microscopy, based on their morphological criteria for fly identification. Four species of the family Calliphoridae [Chrysomya rufifacies (Macquart), Chrysomya megacephala (F.), Chrysomya nigripes Aubertin, and Lucilia cuprina (Wiedemann)] and two species of the family Muscidae [Musca domestica L. and Hydrotaea (=Ophyra) spinigera Stein] were examined in this study, with the features of the anterior Spiracles, dorsal spines between the prothorax and mesothorax, and posterior Spiracles being emphasized. The comparisons, presented herein, should be helpful for forensic practitioners to readily distinguish the third instars of fly species found associated with human cadavers, before their use for further forensic investigations.
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larval ultrastructure of parasarcophaga dux thomson diptera sarcophagidae
Micron, 2003Co-Authors: Kom Sukontason, Kabkaew L. Sukontason, Somsak Piangjai, Hiromu Kurahashi, Tarinee Chaiwong, Noppawan Boonchu, Roy C. VogtsbergerAbstract:Ultrastructure of all larval instars of Parasarcophaga dux (Thomson), a common flesh fly species in Thailand, is presented using scanning electron microscopy. Special attention is given to the structure of anterior and posterior Spiracles since these are important features used to differentiate between other sarcophagids. Each anterior Spiracle in second and third instars has a single row of papillae varying in number from 14 to 17. The posterior spiracular discs have incomplete peritremes, with a prominent inner arc. Three long, narrow spiracular slits are oriented more or less vertically in each spiracular disc of third instar. Posterior spiracular hairs lack extensive branching and emanate approximately midway down the length of each slit. Microscopic morphology of the mouthhooks markedly differs between the first and second instars. The structure of these mouthhooks supports this fly species as being necrophagous or capable of producing myiasis.
Stefan K. Hetz - One of the best experts on this subject based on the ideXlab platform.
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Spiracle activity in moth pupae the role of oxygen and carbon dioxide revisited
Journal of Insect Physiology, 2010Co-Authors: Thomas D Forster, Stefan K. HetzAbstract:Abstract 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 P O 2 and P C O 2 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 P O 2 and P C O 2 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 P C O 2 the minimum P O 2 resulting in open Spiracles was linearly dependent upon P C O 2 . Above a threshold of 1–1.5 kPa CO2 the Spiracles were open irrespective of P O 2 . 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.
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Spiracle activity in moth pupae—The role of oxygen and carbon dioxide revisited
Journal of Insect Physiology, 2009Co-Authors: Thomas D Forster, Stefan K. HetzAbstract:Abstract 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 P O 2 and P C O 2 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 P O 2 and P C O 2 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 P C O 2 the minimum P O 2 resulting in open Spiracles was linearly dependent upon P C O 2 . Above a threshold of 1–1.5 kPa CO2 the Spiracles were open irrespective of P O 2 . 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.
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The role of the Spiracles in gas exchange during development of Samia cynthia (Lepidoptera, Saturniidae) ☆
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2007Co-Authors: Stefan K. HetzAbstract:Abstract 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, CO 2 -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.
Yacine Graba - One of the best experts on this subject based on the ideXlab platform.
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reiterative use of signalling pathways controls multiple cellular events during drosophila posterior Spiracle organogenesis
Developmental Biology, 2010Co-Authors: Corinne Maurelzaffran, Jacques Pradel, Yacine GrabaAbstract:Organogenesis proceeds in multiple steps and events that need to be coordinated in time and space. Yet the genetic and molecular control of such coordination remains poorly understood. In this study we have investigated the contribution of three signalling pathways, Wnt/Wingless (Wg), Hedgehog (Hh), and epidermal growth factor receptor (EGFR), to posterior Spiracle morphogenesis, an organ that forms under Abdominal-B (AbdB) control in the eighth abdominal segment. Using targeted signalling inactivation, we show that these pathways are reiteratively used to control multiple cellular events during posterior Spiracle organogenesis, including cell survival and maintenance of cell polarity and adhesion required for tissue integrity. We propose that the reiterative use of the Wg, Hh, and EGFR signalling pathways serves to coordinate in time and space the sequential deployment of events that collectively allow proper organogenesis.
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hox controlled reorganisation of intrasegmental patterning cues underlies drosophila posterior Spiracle organogenesis
Development, 2005Co-Authors: Samir Merabet, Nan Hu, James Castelli-gair Hombría, Jacques Pradel, Yacine GrabaAbstract:Hox proteins provide axial positional information and control segment morphology in development and evolution. Yet how they specify morphological traits that confer segment identity and how axial positional information interferes with intrasegmental patterning cues during organogenesis remain poorly understood. We have investigated the control of Drosophila posterior Spiracle morphogenesis, a segment-specific structure that forms under Abdominal-B (AbdB) Hox control in the eighth abdominal segment (A8). We show that the Hedgehog (Hh), Wingless (Wg) and Epidermal Growth Factor Receptor (Egfr) pathways provide specific inputs for posterior Spiracle morphogenesis and act in a genetic network made of multiple and rapidly evolving Hox/signalling interplays. A major function of AbdB during posterior Spiracle organogenesis is to reset A8 intrasegmental patterning cues, first by reshaping wg and rhomboid expression patterns, then by reallocating the Hh signal and later by initiating de novo expression of the posterior compartment gene engrailed in anterior compartment cells. These changes in expression patterns confer axial specificity to otherwise reiteratively used segmental patterning cues, linking intrasegmental polarity and acquisition of segment identity.
Timothy J Bradley - One of the best experts on this subject based on the ideXlab platform.
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coordinated ventilation and Spiracle activity produce unidirectional airflow in the hissing cockroach gromphadorhina portentosa
The Journal of Experimental Biology, 2013Co-Authors: Erica C Heinrich, Matthew J Mchenry, Timothy J BradleyAbstract:Insects exchange respiratory gases via an extensive network of tracheal vessels that open to the surface of the body through spiracular valves. Although gas exchange is known to increase with the opening of these Spiracles, it is not clear how this event relates to gas flow through the tracheal system. We examined the relationship between respiratory airflow and Spiracle activity in a ventilating insect, the hissing cockroach, Gromphadorhina portentosa , to better understand the complexity of insect respiratory function. Using simultaneous video recordings of multiple spiracular valves, we found that abdominal Spiracles open and close in unison during periods of ventilation. Additionally, independent recordings of CO2 release from the abdominal and thoracic regions and observations of hyperoxic tracer gas movement indicate that air is drawn into the thoracic Spiracles and expelled from the abdominal Spiracles. Our video recordings suggest that this unidirectional flow is driven by abdominal contractions that occur when the abdominal Spiracles open. The Spiracles then close as the abdomen relaxes and fills with air from the thorax. Therefore, the respiratory system of the hissing cockroach functions as a unidirectional pump through the coordinated action of the Spiracles and abdominal musculature. This mechanism may be employed by a broad diversity of large insects that respire by active ventilation.
Roy C. Vogtsberger - One of the best experts on this subject based on the ideXlab platform.
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Morphological descriptions for the identification of Hypopygiopsis tumrasvini Kurahashi (Diptera: Calliphoridae)
Parasitology Research, 2011Co-Authors: Kittikhun Moophayak, Roy C. Vogtsberger, Kom Sukontason, Kabkaew L. SukontasonAbstract:This article presents morphological descriptions of larvae and adults of Hypopygiopsis tumrasvini Kurahashi (Diptera: Calliphoridae), a blow fly species that may be of forensic importance. Both second and third instar larvae are illustrated, with emphasis placed on important characteristic features used for larval identification, such as the cephalopharyngeal skeleton, anterior and posterior Spiracles, and dorsal spines between the prothorax and mesothorax. Eight to 11 papillae were found on each anterior Spiracle arranged in a single row. The dorsal spines between the prothorax and mesothorax were arranged in sets of posteriorly projecting acuminate spines with darkly pigmented tips. The posterior Spiracles each bear three prominent and separated long, slender spiracular slits encircled by a dark, thick peritreme that is complete ventromedially around a button. Prominent inner projection of peritreme is seen between the middle and lower spiracular slits. A previously published key for differentiating third instar larvae of flies of possible forensic importance in Thailand is updated to include this additional species. Some characteristic features of males and females of the species are also provided.
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Ultrastructure of Spiracles of Musca domestica and Hydrotaea chalcogaster (Diptera: Muscidae)
Parasitology Research, 2006Co-Authors: Rungkanta Methanitikorn, Worachote Boonsriwong, Somsak Piangjai, Hiromu Kurahashi, Roy C. Vogtsberger, Kabkaew L. SukontasonAbstract:Spiracles are major respiratory openings in the exoskeleton of insects. Oxygen, a necessary gas for cell activity, must pass through the Spiracle to enter the respiratory system. In this study, we investigated the fine structure of Spiracles of adult females of Musca domestica L. and Hydrotaea chalcogaster (Wiedemann), both medically important fly species in many parts of the world, by utilizing scanning electron microscopy. The mesothoracic Spiracle of M. domestica is large and elongate-oval in shape, with its anterior end being gradually tapered. The outer surface is densely covered with slender setae of variable distribution and orientation. The metathoracic Spiracle is semicircular or D-shaped, with its rim possessing long, fine, inwardly curved setae. A net-like valve or sieve plate, which has a smooth rim with swollen surface, is located within the atrium of this species. The abdominal Spiracles are circular with a symmetrically swollen peritreme surrounding the opening. The inner filtering apparatus is composed of many spiral tubes, each possessing many small spines. As for H. chalcogaster , the tapering mesothoracic Spiracle is covered with long setae arranged consistently inward from the peritreme, giving it a “combed” appearance. The metathoracic Spiracle is similarly arranged but triangularly rounded in shape, with the anterior and posterior rims possessing long fine setae. The net-like valve within the atrium has a smooth, swollen rim, whereas the inner edge of the atrium bears short, slender setae where it meets with the peritreme of the Spiracle. The abdominal Spiracles of this species look similar to that of M. domestica , with the exception of the filtering apparatus that bears only a few small spines. The function of these Spiracles is discussed.
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larval ultrastructure of parasarcophaga dux thomson diptera sarcophagidae
Micron, 2003Co-Authors: Kom Sukontason, Kabkaew L. Sukontason, Somsak Piangjai, Hiromu Kurahashi, Tarinee Chaiwong, Noppawan Boonchu, Roy C. VogtsbergerAbstract:Ultrastructure of all larval instars of Parasarcophaga dux (Thomson), a common flesh fly species in Thailand, is presented using scanning electron microscopy. Special attention is given to the structure of anterior and posterior Spiracles since these are important features used to differentiate between other sarcophagids. Each anterior Spiracle in second and third instars has a single row of papillae varying in number from 14 to 17. The posterior spiracular discs have incomplete peritremes, with a prominent inner arc. Three long, narrow spiracular slits are oriented more or less vertically in each spiracular disc of third instar. Posterior spiracular hairs lack extensive branching and emanate approximately midway down the length of each slit. Microscopic morphology of the mouthhooks markedly differs between the first and second instars. The structure of these mouthhooks supports this fly species as being necrophagous or capable of producing myiasis.
