Pub Date : 2022-11-01DOI: 10.1016/j.asd.2022.101212
Wenjing Xu , Guoyun Zhang , Liangliang Zhang , Xiaolei Wang , Johan Billen , Hong He
The prepharyngeal gland (prePG) and pharyngeal gland (PG) make up the largest exocrine structures in the head of the ant Camponotus japonicus. We used microscopy to study the histological and ultrastructural features of both glands in different castes. The number of secretory units in the prePG is considerably higher than in other ant species and shows a complex duct system which is made up by duct cells, secondary ducts and a main duct. These lead the secretions of hundreds to thousands of secretory cells into the prepharynx through a modified sieve plate at each side. The glove-shaped PG shows clear caste differences in tubule number. The ultrastructure of both the prePG and PG shows abundant mitochondria and secretion vesicles. Moreover, the prePG is loaded with rough endoplasmic reticulum (RER) which means its main secretions are proteinaceous compounds, while the PG is dominated by smooth endoplasmic reticulum (SER) which means the main secretions are lipids. The morphological differences like cell number of the prePG and tubule number of the PG indicate different secretory abilities of each caste. We for the first time introduce histology-based relative size to indicate secretory activity. The proportionally high development of the prePG in minor workers supports a role in trophallaxis.
{"title":"Morphology and ultrastructure of the prepharyngeal and pharyngeal glands in the ant Camponotus japonicus","authors":"Wenjing Xu , Guoyun Zhang , Liangliang Zhang , Xiaolei Wang , Johan Billen , Hong He","doi":"10.1016/j.asd.2022.101212","DOIUrl":"10.1016/j.asd.2022.101212","url":null,"abstract":"<div><p>The prepharyngeal gland (prePG) and pharyngeal gland (PG) make up the largest exocrine structures in the head of the ant <span><em>Camponotus</em><em> japonicus</em></span><span>. We used microscopy to study the histological and ultrastructural features of both glands in different castes. The number of secretory units in the prePG is considerably higher than in other ant species and shows a complex duct system which is made up by duct cells, secondary ducts and a main duct. These lead the secretions of hundreds to thousands of secretory cells into the prepharynx through a modified sieve plate<span><span> at each side. The glove-shaped PG shows clear caste differences in tubule number. The ultrastructure of both the prePG and PG shows abundant mitochondria and secretion vesicles. Moreover, the prePG is loaded with rough endoplasmic reticulum<span> (RER) which means its main secretions are proteinaceous compounds, while the PG is dominated by smooth endoplasmic reticulum (SER) which means the main secretions are </span></span>lipids<span>. The morphological differences like cell number of the prePG and tubule number of the PG indicate different secretory abilities of each caste. We for the first time introduce histology-based relative size to indicate secretory activity. The proportionally high development of the prePG in minor workers supports a role in trophallaxis.</span></span></span></p></div>","PeriodicalId":55461,"journal":{"name":"Arthropod Structure & Development","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40650974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-01DOI: 10.1016/j.asd.2022.101214
Chirlei D. de Brito , Geane de O. Lanes , Celso O. Azevedo
The mesopleuron of Bethylidae has morphostructural characters that remain poorly understood, explored, and defined. The wide range of variability of this sclerite has generated confusion both in taxonomic and cladistic studies. Aiming to solve this issue, we describe the general mesopleural anatomy of Bethylidae. Our goal is to propose primary homologies by matching external and internal structures (muscles and apodemes). We reconstruct the ancestral state of the main mesopleural structures by applying the maximum-likelihood method on ten selected character states. The phylogeny of Bethylidae is built by analyzing a dataset of COI and 28S sequences, using maximum-likelihood and Bayesian inference methods. The Bethylidae and all subfamilies are recovered as monophyletic in both resulting phylogenies, with high clade support values. Although the two analyses yielded similar results, we used the tree resulting from the Bayesian inference to map the evolution of the morphological characters, as it is better supported. The study of mesopleural anatomy allows exploration and discussion of the evolution of characters and their present states in Bethylidae and Hymenoptera in general. Reconstruction of the ancestral states shows that many characters arose independently in Bethylidae subfamilies.
{"title":"Morphology and evolution of the mesopleuron in Bethylidae (Hymenoptera: Chrysidoidea) mapped on a molecular phylogeny","authors":"Chirlei D. de Brito , Geane de O. Lanes , Celso O. Azevedo","doi":"10.1016/j.asd.2022.101214","DOIUrl":"10.1016/j.asd.2022.101214","url":null,"abstract":"<div><p><span>The mesopleuron of Bethylidae has morphostructural characters that remain poorly understood, explored, and defined. The wide range of variability of this sclerite has generated confusion both in taxonomic and cladistic studies. Aiming to solve this issue, we describe the general mesopleural anatomy of Bethylidae. Our goal is to propose primary homologies by matching external and internal structures (muscles and apodemes). We reconstruct the ancestral state of the main mesopleural structures by applying the maximum-likelihood method on ten selected character states. The phylogeny of Bethylidae is built by analyzing a dataset of </span>COI<span> and 28S sequences, using maximum-likelihood and Bayesian inference methods. The Bethylidae and all subfamilies are recovered as monophyletic in both resulting phylogenies, with high clade support values. Although the two analyses yielded similar results, we used the tree resulting from the Bayesian inference to map the evolution of the morphological characters<span>, as it is better supported. The study of mesopleural anatomy allows exploration and discussion of the evolution of characters and their present states in Bethylidae and Hymenoptera in general. Reconstruction of the ancestral states shows that many characters arose independently in Bethylidae subfamilies.</span></span></p></div>","PeriodicalId":55461,"journal":{"name":"Arthropod Structure & Development","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40455584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
During evolution, various lineages of arthropods colonized land and independently acquired air-breathing organs. Some taxa of oniscidean isopods (Crustacea, Isopoda, Oniscidea) are the most successful crustacean lineages on land and possess organs called “lungs” or “pseudotrachea” for air-breathing in their abdominal appendages, i.e., in pleopods. Although these lungs are important for adapting to the terrestrial environment, their developmental process has not yet been elucidated. In the present study, we investigated the process of lung development in Porcellio scaber, the common rough woodlouse with pleopodal lungs in the first two pairs of pleopods. The lungs in the second pleopods developed at the manca 1 stage (immediately after hatching) and became functional at the manca 2 stage. In the first pleopods, which appear at the manca 3 stage, the lungs were gradually developed during the manca 3 stage and became functional in post-manca juveniles. In the second pleopods, epithelial invaginations led to lung development. These results suggest that some novel developmental mechanisms with epithelial invaginations and cuticle formation were acquired during terrestrialization, resulting in the development of functional lungs in the terrestrial isopod lineages.
{"title":"Pleopodal lung development in a terrestrial isopod, Porcellio scaber (Oniscidea)","authors":"Naoto Inui, Ryosuke Kimbara, Haruka Yamaguchi, Toru Miura","doi":"10.1016/j.asd.2022.101210","DOIUrl":"10.1016/j.asd.2022.101210","url":null,"abstract":"<div><p><span>During evolution, various lineages of arthropods colonized land and independently acquired air-breathing organs. Some taxa of oniscidean isopods (Crustacea, Isopoda, Oniscidea) are the most successful crustacean lineages on land and possess organs called “lungs” or “pseudotrachea” for air-breathing in their abdominal appendages, i.e., in pleopods. Although these lungs are important for adapting to the terrestrial environment, their developmental process has not yet been elucidated. In the present study, we investigated the process of lung development in </span><span><em>Porcellio scaber</em></span><span>, the common rough woodlouse with pleopodal lungs in the first two pairs of pleopods. The lungs in the second pleopods developed at the manca<span> 1 stage (immediately after hatching) and became functional at the manca 2 stage. In the first pleopods, which appear at the manca 3 stage, the lungs were gradually developed during the manca 3 stage and became functional in post-manca juveniles. In the second pleopods, epithelial invaginations led to lung development. These results suggest that some novel developmental mechanisms with epithelial invaginations and cuticle formation were acquired during terrestrialization, resulting in the development of functional lungs in the terrestrial isopod lineages.</span></span></p></div>","PeriodicalId":55461,"journal":{"name":"Arthropod Structure & Development","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33492199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-01DOI: 10.1016/j.asd.2022.101203
Vukica D. Vujić, Bojan S. Ilić, Luka R. Lučić, Zvezdana S. Jovanović, Jelena Z. Milovanović, Boris D. Dudić, Dalibor Z. Stojanović
The presence of morphological integration and modularity of the forcipular apparatus, despite its evolutionary significance, has not been analyzed in centipedes. This morphological structure has a crucial role in feeding and defense, thanks to its poisonous part (forcipules), which is important for catching the prey. The aims of our study were: i) to test the hypothesis of modularity of the forcipular apparatus in centipede Lithobius melanops; and ii) to investigate the influence of allometry on overall morphological integration in the aforementioned species using a geometric morphometric approach. The presence of fluctuating asymmetry was obtained by Procrustes ANOVA. Allometry was significant only for the symmetric component of the forcipular apparatus. The modularity hypothesis was not accepted, because the covariance coefficients for symmetric and asymmetric components were lower than 89.5% and 72.1% (respectively) of other RV coefficients obtained by a random contiguous partition of the forcipular apparatus. Results of the present study indicate that allometry does increase the level of morphological integration in the forcipular apparatus. According to our results, the forcipular coxosternite and forcipules could not be considered as separate modules; namely, they probably share similar developmental pathways and function in different forms of behavior and survival in L. melanops.
{"title":"Presence of morphological integration and modularity of the forcipular apparatus in Lithobius melanops (Chilopoda: Lithobiomorpha: Lithobiidae)","authors":"Vukica D. Vujić, Bojan S. Ilić, Luka R. Lučić, Zvezdana S. Jovanović, Jelena Z. Milovanović, Boris D. Dudić, Dalibor Z. Stojanović","doi":"10.1016/j.asd.2022.101203","DOIUrl":"10.1016/j.asd.2022.101203","url":null,"abstract":"<div><p>The presence of morphological integration and modularity of the forcipular apparatus, despite its evolutionary significance, has not been analyzed in centipedes. This morphological structure has a crucial role in feeding and defense, thanks to its poisonous part (forcipules), which is important for catching the prey. The aims of our study were: i) to test the hypothesis of modularity of the forcipular apparatus in centipede <span><em>Lithobius</em><em> melanops</em></span><span>; and ii) to investigate the influence of allometry on overall morphological integration in the aforementioned species using a geometric morphometric approach. The presence of fluctuating asymmetry was obtained by Procrustes ANOVA. Allometry was significant only for the symmetric component of the forcipular apparatus. The modularity hypothesis was not accepted, because the covariance coefficients for symmetric and asymmetric components were lower than 89.5% and 72.1% (respectively) of other RV coefficients obtained by a random contiguous partition of the forcipular apparatus. Results of the present study indicate that allometry does increase the level of morphological integration in the forcipular apparatus. According to our results, the forcipular coxosternite and forcipules could not be considered as separate modules; namely, they probably share similar developmental pathways and function in different forms of behavior and survival in </span><em>L. melanops</em>.</p></div>","PeriodicalId":55461,"journal":{"name":"Arthropod Structure & Development","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33458494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-01DOI: 10.1016/j.asd.2022.101215
Luiza Helena Bueno da Silva , Julia Ayumi Ando Teixeira , Lara Teixeira Laranjo , Ana Maria Costa-Leonardo , Edward L. Vargo , Ives Haifig
In termites, the maturation of the female reproductive system is progressive following post-embryonic development. In Silvestritermes euamignathus, the imaginal line is characterized by five nymphal instars that develop into the imago, but it can deviate in some instars to neotenic reproductives. In order to understand the rate of development of the female reproductive system throughout post-embryonic development, we analyzed the morphology of the reproductive system of nymphs, characterizing the stage of development and comparing it with neotenics and primary queens. We also followed embryonic development and compared eggs from neotenics and primary queens from incipient and mature colonies. Our results showed that gonadal development follows the post-embryonic instars, and previtellogenic oocytes are present in third-instar nymphs and are retained for the next two successive nymphal instars. The full maturation of the ovaries with vitellogenic oocytes requires molting to either imagos or neotenics. Eggs from neotenics follow the same embryonic development and each stage presents similar volume when compared to those of mature primary queens. Eggs of primary queens from incipient colonies are greater in volume than those of mature primary queens and of neotenics, suggesting an investment in egg quality rather than quantity during colony foundation.
{"title":"Post-embryonic development of the female reproductive system of the Neotropical termite Silvestritermes euamignathus (Isoptera: Termitidae: Syntermitinae)","authors":"Luiza Helena Bueno da Silva , Julia Ayumi Ando Teixeira , Lara Teixeira Laranjo , Ana Maria Costa-Leonardo , Edward L. Vargo , Ives Haifig","doi":"10.1016/j.asd.2022.101215","DOIUrl":"10.1016/j.asd.2022.101215","url":null,"abstract":"<div><p><span><span>In termites, the maturation of the </span>female reproductive system is progressive following post-embryonic development. In </span><em>Silvestritermes euamignathus</em><span><span>, the imaginal line is characterized by five nymphal instars that develop into the imago, but it can deviate in some instars to neotenic reproductives. In order to understand the rate of development of the female reproductive system throughout post-embryonic development, we analyzed the morphology of the reproductive system of nymphs, characterizing the stage of development and comparing it with neotenics and primary queens. We also followed </span>embryonic development<span> and compared eggs from neotenics and primary queens from incipient and mature colonies. Our results showed that gonadal development<span> follows the post-embryonic instars, and previtellogenic oocytes are present in third-instar nymphs and are retained for the next two successive nymphal instars. The full maturation of the ovaries with vitellogenic oocytes requires molting to either imagos or neotenics. Eggs from neotenics follow the same embryonic development and each stage presents similar volume when compared to those of mature primary queens. Eggs of primary queens from incipient colonies are greater in volume than those of mature primary queens and of neotenics, suggesting an investment in egg quality rather than quantity during colony foundation.</span></span></span></p></div>","PeriodicalId":55461,"journal":{"name":"Arthropod Structure & Development","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40569823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-01DOI: 10.1016/j.asd.2022.101211
Roman Rakitov
The flat bugs, Aradidae, have exceptionally long piercing-sucking stylets coiled up at rest in the anterior part of the head. Previous studies suggested that the majority of aradids can be divided into two groups by the direction of stylet coiling, clockwise or anticlockwise. Detailed reconstruction of the head skeleton and musculature from series of polished sections, examined in SEM, of epon-embedded specimens of three species has shown that these groups represent two disparate modifications of the head groundplan. In Aradus betulae (L.), the stylet coil is accommodated inside the greatly enlarged anteclypeus within an expansible membranous diverticulum of its epipharyngeal cuticle. In contrast, in Isodermus planus Erichson and Carventus brachypterus Kormilev, the coil lies freely underneath the anteclypeus between the extended maxillary lobes (in I. planus fused with the extended gular lobe). The intraclypeal coils occur in the subfamilies Aradinae, Calisiinae, and Chinamyersiinae and the subclypeal coils in Isoderminae, Carventinae, Mezirinae, Aneurinae, Prosympiestinae, and possibly in the closely related family Termitaphididae. Each method of stylet coiling is associated with a suite of divergently specialized structural traits, suggesting that the two groups have independently evolved from ancestors endowed with regular stylets. Functional mechanics of the coiled stylet bundles are discussed.
{"title":"The mouthparts of the Aradidae (Insecta: Hemiptera: Heteroptera)","authors":"Roman Rakitov","doi":"10.1016/j.asd.2022.101211","DOIUrl":"10.1016/j.asd.2022.101211","url":null,"abstract":"<div><p><span><span>The flat bugs, Aradidae, have exceptionally long piercing-sucking stylets coiled up at rest in the anterior part of the head. Previous studies suggested that the majority of aradids can be divided into two groups by the direction of stylet coiling, clockwise or anticlockwise. Detailed reconstruction of the head skeleton and musculature from series of polished sections, examined in </span>SEM, of epon-embedded specimens of three species has shown that these groups represent two disparate modifications of the head groundplan. In </span><em>Aradus betulae</em> (L.), the stylet coil is accommodated inside the greatly enlarged anteclypeus within an expansible membranous diverticulum of its epipharyngeal cuticle. In contrast, in <em>Isodermus planus</em> Erichson and <em>Carventus brachypterus</em> Kormilev, the coil lies freely underneath the anteclypeus between the extended maxillary lobes (in <em>I. planus</em> fused with the extended gular lobe). The intraclypeal coils occur in the subfamilies Aradinae, Calisiinae, and Chinamyersiinae and the subclypeal coils in Isoderminae, Carventinae, Mezirinae, Aneurinae, Prosympiestinae, and possibly in the closely related family Termitaphididae. Each method of stylet coiling is associated with a suite of divergently specialized structural traits, suggesting that the two groups have independently evolved from ancestors endowed with regular stylets. Functional mechanics of the coiled stylet bundles are discussed.</p></div>","PeriodicalId":55461,"journal":{"name":"Arthropod Structure & Development","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40655273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-01DOI: 10.1016/j.asd.2022.101202
Silvio S. Nihei , Genting Liu , Qike Wang , Xianui Liu , Xinyu Li , Xiunan Pang , Deivys Alvarez-Garcia , Dong Zhang
Tachinidae are one of the most diverse clades of Diptera. All tachinids are parasitoids of insects and other arthropods, and thus are considered an important source of biological pest control. Antennae are the most important olfactory organs of Tachinidae playing key roles in their lives, especially in locating hosts, and details of antennal ultrastructure could provide useful features for phylogenetic studies and understanding their adaptive evolution. Despite the ecological and evolutionary importance of antennae, the current knowledge of antennal ultrastructure is scarce for Tachinidae. Our study examined antennal sensilla of thirteen species belonging to thirteen genera within eleven tribes of all the four subfamilies (Phasiinae, Dexiinae, Tachininae, and Exoristinae): Beskia aelops Walker, Trichodura sp., Voria ruralis (Fallén), Zelia sp., Cylindromyia carinata Townsend, Phasia xenos Townsend, Neomintho sp., Genea australis (Townsend), Copecrypta sp., Hystricia sp., Belvosia sp., Leschenaultia sp., and Winthemia pinguis (Fabricius). Types, length and distribution of antennal sensilla were investigated via scanning electron microscopy (SEM). Our comparative analysis summarized 29 variable characters and we evaluated their phylogenetic signal for subfamilial, tribal and generic/specific levels, showing that antennal ultrastructure could be a reliable source of characters for phylogenetic analysis. Our findings demonstrate the remarkable diversity of the antennal ultrastructure of Tachinidae.
{"title":"Comparative morphology of antennal ultrastructure in Tachinidae parasitoid flies (Diptera): The phylogenetic importance of antennal sensilla","authors":"Silvio S. Nihei , Genting Liu , Qike Wang , Xianui Liu , Xinyu Li , Xiunan Pang , Deivys Alvarez-Garcia , Dong Zhang","doi":"10.1016/j.asd.2022.101202","DOIUrl":"10.1016/j.asd.2022.101202","url":null,"abstract":"<div><p><span><span><span>Tachinidae<span> are one of the most diverse clades of Diptera. All tachinids are parasitoids<span> of insects and other arthropods, and thus are considered an important source of biological pest control<span>. Antennae are the most important olfactory organs of Tachinidae playing key roles in their lives, especially in locating hosts, and details of antennal ultrastructure could provide useful features for </span></span></span></span>phylogenetic studies and understanding their adaptive evolution. Despite the ecological and evolutionary importance of antennae, the current knowledge of antennal ultrastructure is scarce for Tachinidae. Our study examined antennal </span>sensilla of thirteen species belonging to thirteen genera within eleven tribes of all the four subfamilies (Phasiinae, Dexiinae, Tachininae, and Exoristinae): </span><em>Beskia aelops</em> Walker, <em>Trichodura</em> sp., <em>Voria ruralis</em> (Fallén), <em>Zelia</em> sp., <em>Cylindromyia carinata</em> Townsend, <em>Phasia xenos</em> Townsend, <em>Neomintho</em> sp., <span><em>Genea</em><em> australis</em></span> (Townsend), <em>Copecrypta</em> sp., <em>Hystricia</em> sp., <em>Belvosia</em> sp., <em>Leschenaultia</em> sp., and <em>Winthemia pinguis</em><span> (Fabricius). Types, length and distribution of antennal sensilla were investigated via scanning electron microscopy (SEM). Our comparative analysis summarized 29 variable characters and we evaluated their phylogenetic signal for subfamilial, tribal and generic/specific levels, showing that antennal ultrastructure could be a reliable source of characters for phylogenetic analysis. Our findings demonstrate the remarkable diversity of the antennal ultrastructure of Tachinidae.</span></p></div>","PeriodicalId":55461,"journal":{"name":"Arthropod Structure & Development","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33445637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Homology of the posterior midgut regions (PMG) in different phylogenetic lineages of acariform mites (superorder Acariformes) remains unresolved. In the order Trombidiformes, the ultrastructure of the PMG is known primarily in derived groups; thus this study focuses on species belonging to a relatively basal trombidiform family. PMG of Anystis baccarum consists of the colon and postcolon separated by a small intercolon. The fine structure of the colon and postcolon is close to that of the corresponding organs of sarcoptiform mites with the epithelium showing absorptive and endocytotic activity. The epithelial cells produce a variety of excretory vacuoles and a peritrophic matrix around the feces. Morover, the epithelium of the postcolon is characterized by the highest apical brush border and especially numerous mitochondria suggesting involvement in water and ion absorption. The intercolon functions as a sphincter lined with an epithelium capable of producing excretory granules. A pair of short blind extensions arises assimmetrically from the intercolon into the body cavity. Ultrastructurally, these extensions are similar to the arachnid Malpighian tubules and may be their reduced version. Rare endocrine-like cells have been observed in the colon and postcolon.
{"title":"Fine structure of the posterior midgut in the mite Anystis baccarum (L.).","authors":"S. Filimonova","doi":"10.2139/ssrn.4187451","DOIUrl":"https://doi.org/10.2139/ssrn.4187451","url":null,"abstract":"Homology of the posterior midgut regions (PMG) in different phylogenetic lineages of acariform mites (superorder Acariformes) remains unresolved. In the order Trombidiformes, the ultrastructure of the PMG is known primarily in derived groups; thus this study focuses on species belonging to a relatively basal trombidiform family. PMG of Anystis baccarum consists of the colon and postcolon separated by a small intercolon. The fine structure of the colon and postcolon is close to that of the corresponding organs of sarcoptiform mites with the epithelium showing absorptive and endocytotic activity. The epithelial cells produce a variety of excretory vacuoles and a peritrophic matrix around the feces. Morover, the epithelium of the postcolon is characterized by the highest apical brush border and especially numerous mitochondria suggesting involvement in water and ion absorption. The intercolon functions as a sphincter lined with an epithelium capable of producing excretory granules. A pair of short blind extensions arises assimmetrically from the intercolon into the body cavity. Ultrastructurally, these extensions are similar to the arachnid Malpighian tubules and may be their reduced version. Rare endocrine-like cells have been observed in the colon and postcolon.","PeriodicalId":55461,"journal":{"name":"Arthropod Structure & Development","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45545027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The flat bugs, Aradidae, have exceptionally long piercing-sucking stylets coiled up at rest in the anterior part of the head. Previous studies suggested that the majority of aradids can be divided into two groups by the direction of stylet coiling, clockwise or anticlockwise. Detailed reconstruction of the head skeleton and musculature from series of polished sections, examined in SEM, of epon-embedded specimens of three species has shown that these groups represent two disparate modifications of the head groundplan. In Aradus betulae (L.), the stylet coil is accommodated inside the greatly enlarged anteclypeus within an expansible membranous diverticulum of its epipharyngeal cuticle. In contrast, in Isodermus planus Erichson and Carventus brachypterus Kormilev, the coil lies freely underneath the anteclypeus between the extended maxillary lobes (in I. planus fused with the extended gular lobe). The intraclypeal coils occur in the subfamilies Aradinae, Calisiinae, and Chinamyersiinae and the subclypeal coils in Isoderminae, Carventinae, Mezirinae, Aneurinae, Prosympiestinae, and possibly in the closely related family Termitaphididae. Each method of stylet coiling is associated with a suite of divergently specialized structural traits, suggesting that the two groups have independently evolved from ancestors endowed with regular stylets. Functional mechanics of the coiled stylet bundles are discussed.
{"title":"The mouthparts of the Aradidae (Insecta: Hemiptera: Heteroptera).","authors":"R. Rakitov","doi":"10.2139/ssrn.4063466","DOIUrl":"https://doi.org/10.2139/ssrn.4063466","url":null,"abstract":"The flat bugs, Aradidae, have exceptionally long piercing-sucking stylets coiled up at rest in the anterior part of the head. Previous studies suggested that the majority of aradids can be divided into two groups by the direction of stylet coiling, clockwise or anticlockwise. Detailed reconstruction of the head skeleton and musculature from series of polished sections, examined in SEM, of epon-embedded specimens of three species has shown that these groups represent two disparate modifications of the head groundplan. In Aradus betulae (L.), the stylet coil is accommodated inside the greatly enlarged anteclypeus within an expansible membranous diverticulum of its epipharyngeal cuticle. In contrast, in Isodermus planus Erichson and Carventus brachypterus Kormilev, the coil lies freely underneath the anteclypeus between the extended maxillary lobes (in I. planus fused with the extended gular lobe). The intraclypeal coils occur in the subfamilies Aradinae, Calisiinae, and Chinamyersiinae and the subclypeal coils in Isoderminae, Carventinae, Mezirinae, Aneurinae, Prosympiestinae, and possibly in the closely related family Termitaphididae. Each method of stylet coiling is associated with a suite of divergently specialized structural traits, suggesting that the two groups have independently evolved from ancestors endowed with regular stylets. Functional mechanics of the coiled stylet bundles are discussed.","PeriodicalId":55461,"journal":{"name":"Arthropod Structure & Development","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2022-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41574099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wenjing Xu, Guoyun Zhang, Liangliang Zhang, Xiaolei Wang, J. Billen, H. He
The prepharyngeal gland (prePG) and pharyngeal gland (PG) make up the largest exocrine structures in the head of the ant Camponotus japonicus. We used microscopy to study the histological and ultrastructural features of both glands in different castes. The number of secretory units in the prePG is considerably higher than in other ant species and shows a complex duct system which is made up by duct cells, secondary ducts and a main duct. These lead the secretions of hundreds to thousands of secretory cells into the prepharynx through a modified sieve plate at each side. The glove-shaped PG shows clear caste differences in tubule number. The ultrastructure of both the prePG and PG shows abundant mitochondria and secretion vesicles. Moreover, the prePG is loaded with rough endoplasmic reticulum (RER) which means its main secretions are proteinaceous compounds, while the PG is dominated by smooth endoplasmic reticulum (SER) which means the main secretions are lipids. The morphological differences like cell number of the prePG and tubule number of the PG indicate different secretory abilities of each caste. We for the first time introduce histology-based relative size to indicate secretory activity. The proportionally high development of the prePG in minor workers supports a role in trophallaxis.
{"title":"Morphology and ultrastructure of the prepharyngeal and pharyngeal glands in the ant Camponotus japonicus.","authors":"Wenjing Xu, Guoyun Zhang, Liangliang Zhang, Xiaolei Wang, J. Billen, H. He","doi":"10.2139/ssrn.4157419","DOIUrl":"https://doi.org/10.2139/ssrn.4157419","url":null,"abstract":"The prepharyngeal gland (prePG) and pharyngeal gland (PG) make up the largest exocrine structures in the head of the ant Camponotus japonicus. We used microscopy to study the histological and ultrastructural features of both glands in different castes. The number of secretory units in the prePG is considerably higher than in other ant species and shows a complex duct system which is made up by duct cells, secondary ducts and a main duct. These lead the secretions of hundreds to thousands of secretory cells into the prepharynx through a modified sieve plate at each side. The glove-shaped PG shows clear caste differences in tubule number. The ultrastructure of both the prePG and PG shows abundant mitochondria and secretion vesicles. Moreover, the prePG is loaded with rough endoplasmic reticulum (RER) which means its main secretions are proteinaceous compounds, while the PG is dominated by smooth endoplasmic reticulum (SER) which means the main secretions are lipids. The morphological differences like cell number of the prePG and tubule number of the PG indicate different secretory abilities of each caste. We for the first time introduce histology-based relative size to indicate secretory activity. The proportionally high development of the prePG in minor workers supports a role in trophallaxis.","PeriodicalId":55461,"journal":{"name":"Arthropod Structure & Development","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2022-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44071997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}