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1.
PLoS One ; 15(3): e0229120, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32130246

RESUMO

A remarkable new genus and species of Nemourinae, Sinonemura balangshana gen. et sp. n., is described from Balang Mountains, Sichuan, southwestern China. The description is based on morphology and molecular data. The Nemourinae genera related to the new taxon are re-evaluated on the basis of comparative functional morphology of male epiproct. Notes on the Asian distribution of the Nemourinae are also given.


Assuntos
Insetos/classificação , Neópteros/classificação , Filogenia , Distribuição Animal , Animais , China , Classificação/métodos , Demografia , Feminino , Especiação Genética , Cabeça/anatomia & histologia , Cabeça/crescimento & desenvolvimento , Insetos/anatomia & histologia , Insetos/crescimento & desenvolvimento , Masculino , Neópteros/anatomia & histologia , Neópteros/crescimento & desenvolvimento , Especificidade da Espécie , Asas de Animais/anatomia & histologia , Asas de Animais/crescimento & desenvolvimento
2.
Annu Rev Entomol ; 65: 121-143, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31585504

RESUMO

Although the insect circulatory system is involved in a multitude of vital physiological processes, it has gone grossly understudied. This review highlights this critical physiological system by detailing the structure and function of the circulatory organs, including the dorsal heart and the accessory pulsatile organs that supply hemolymph to the appendages. It also emphasizes how the circulatory system develops and ages and how, by means of reflex bleeding and functional integration with the immune system, it supports mechanisms for defense against predators and microbial invaders, respectively. Beyond that, this review details evolutionary trends and novelties associated with this system, as well as the ways in which this system also plays critical roles in thermoregulation and tracheal ventilation in high-performance fliers. Finally, this review highlights how novel discoveries could be harnessed for the control of vector-borne diseases and for translational medicine, and it details principal knowledge gaps that necessitate further investigation.


Assuntos
Insetos/fisiologia , Envelhecimento/fisiologia , Animais , Evolução Biológica , Regulação da Temperatura Corporal , Sistema Cardiovascular , Hemolinfa/fisiologia , Sistema Imunitário , Insetos/anatomia & histologia , Metamorfose Biológica
3.
Arthropod Struct Dev ; 52: 100881, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31473469

RESUMO

The morphology of the prognathous, host-seeking first-instar larvae of Stylops advarians was examined to advance our understanding of their adaptations to reach immature bee hosts, a process requiring temporal phoresy on an adult bee. Sensory structures on the larval head, including eye spots and two pairs of olfactory pits, evidently assist recognition of an adult bee and eventual detection of a permanent host within a nest cell. First-instar larvae utilize various features of their appendages to travel securely on their phoretic host. Flexible adhesive tarsi of the pro- and mesothoracic legs allow them to embark and be retained on a flying bee. The tips of the pair of caudal filaments appear modified for a similar purpose. Spinulae of two lengths, and arranged in distinct patterns, cover the posterior edges of the thoracic and abdominal segments both dorsally and ventrally. These projections can cause lodging of larvae in the plumose hairs of the phoretic host, and may lock into the exine of pollen collected by the foraging bee. Discovery of a first-instar larva partially packed into a pollen load and in the crop of Andrena milwaukeensis demonstrates that Stylops is adapted to travel with a phoretic host both externally and internally.


Assuntos
Abelhas/parasitologia , Interações Hospedeiro-Parasita , Insetos/anatomia & histologia , Animais , Insetos/crescimento & desenvolvimento , Insetos/fisiologia , Insetos/ultraestrutura , Larva/anatomia & histologia , Larva/crescimento & desenvolvimento , Larva/fisiologia , Larva/ultraestrutura , Microscopia Eletrônica de Varredura
4.
Cell Tissue Res ; 377(3): 505-525, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31359140

RESUMO

The insect midgut epithelium represents an interface between the internal and the external environment and it is the almost unique epithelial tissue by which these arthropods acquire nutrients. This epithelium is indeed able to produce digestive enzymes and to support vectorial transport of small organic nutrients, ions, and water. Moreover, it plays a key role in the defense against pathogenic microorganisms and in shaping gut microbiota. Another important midgut function is the ability to produce signaling molecules that regulate its own physiology and the activity of other organs. The two main mature cell types present in the midgut of all insects, i.e., columnar and endocrine cells, are responsible for these functions. In addition, stem cells, located at the base of the midgut epithelium, ensure the growth and renewal of the midgut during development and after injury. In insects belonging to specific orders, midgut physiology is deeply conditioned by the presence of unique cell types, i.e., goblet and copper cells, which confer peculiar features to this organ. This review reports current knowledge on the cells that form the insect midgut epithelium, focusing attention on their morphological and functional features. Notwithstanding the apparent structural simplicity of this organ, the properties of the cells make the midgut a key player in insect development and homeostasis.


Assuntos
Sistema Digestório/ultraestrutura , Endoderma/ultraestrutura , Insetos/anatomia & histologia , Animais
6.
Bioinspir Biomim ; 14(5): 056005, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31239412

RESUMO

In this paper, the controlled stability of insect hovering flight is analyzed in detail based on a simplified dynamic model of the flyer and flow. The simplified dynamic model incorporates PID-based wing-kinematic controllers. The control stability of the hovering flight is evaluated based on the cycle-mean dynamic equations. The stability analyses and the simplified dynamic model allow us to derive and test the control coefficients for stable free hovering, firstly in the longitudinal mode of flight and then the lateral mode. In this manner, coefficients for wing-kinematic control for full CFD-FSI simulation could be obtained very efficiently. The coefficients thus determined are verified against full-fidelity CFD-FSI free flight simulations.


Assuntos
Voo Animal/fisiologia , Insetos/fisiologia , Modelos Biológicos , Asas de Animais/fisiologia , Animais , Fenômenos Biomecânicos , Insetos/anatomia & histologia , Movimento (Física) , Asas de Animais/anatomia & histologia
7.
Curr Biol ; 29(9): R306-R309, 2019 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-31063717

RESUMO

Jakub Prokop and Michael Engel introduce palaeodictyopterids, a very diverse extinct lineage of insects.


Assuntos
Evolução Biológica , Fósseis/anatomia & histologia , Insetos/anatomia & histologia , Insetos/fisiologia , Animais
8.
Integr Comp Biol ; 59(2): 410-419, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31120505

RESUMO

Many species have evolved alternate phenotypes, thus enabling individuals to conditionally produce phenotypes that are favorable for reproductive success. Examples of this phenomenon include sexual dimorphism, alternative reproductive strategies, and social insect castes. While the evolutionary functions and developmental mechanisms of dimorphic phenotypes have been studied extensively, little attention has focused on the evolutionary covariance between each phenotype. We extend the conceptual framework and methods of morphological integration to hypothesize that dimorphic traits tend to be less integrated between sexes or social castes. In the case of social insects, we describe results from our recent study of an ant genus in which workers have major and minor worker castes that perform different behavioral repertoires in and around the nest. In the case of birds, we describe a new analysis of a family of songbirds that exhibits plumage coloration that can differ greatly between males and females, with apparently independent changes in each sex. Ant head shape, which is highly specialized in each worker caste, was weakly integrated between worker castes, whereas thorax shape, which is more monomorphic, was tightly integrated. Similarly, in birds, we found a negative association between dimorphism and the degree of integration between sexes. We also found that integration decreased in fairy wrens (Malurus) for many feather patches that evolved greater dichromatism. Together, this suggests that the process of evolving increased dimorphism results in a decrease in integration between sexes and social castes. We speculate that once a mechanism for dimorphism evolves, that mechanism can create independent variation in one sex or caste upon which selection may act.


Assuntos
Evolução Biológica , Insetos/anatomia & histologia , Insetos/fisiologia , Traços de História de Vida , Animais , Caracteres Sexuais , Comportamento Social
9.
Cell Tissue Res ; 377(3): 397-414, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31037358

RESUMO

Insects are the most abundant and diverse class of animals on the planet. One explanation for their success is their extraordinary ability to successfully consume a wide range of foods. Like all heterotrophic organisms, insects need to acquire vital nutrients from their diet. The central organ for food digestion and absorption of nutrients is the gastrointestinal tract. This organ's principal functions are mediating the efficient digestion of the diet and protecting the organism against harmful chemicals, microorganisms, and mechanical damage from the food. These functions are achieved through regional differentiation of the alimentary canal as well as highly flexible adaptations to the consumed diets, both at anatomical and molecular levels. Numerous studies describing the general gut morphology and associated digestive mechanisms of various insects exist. Nevertheless, the molecular patterns underlying digestion and nutrient uptake in insects are still poorly characterized. This review aims to provide an overview of the general strategies of extracellular macronutrient digestion and consequent nutrient absorption found among different orders of insects.


Assuntos
Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/ultraestrutura , Insetos/anatomia & histologia , Insetos/metabolismo , Animais , Metabolismo dos Carboidratos , Digestão , Metabolismo dos Lipídeos , Proteínas/metabolismo
11.
Nat Commun ; 10(1): 1235, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30874563

RESUMO

Long-proboscid scorpionflies are enigmatic, mid-Mesozoic insects associated with gymnosperm pollination. One major lineage, Aneuretopsychina, consists of four families plus two haustellate clades, Diptera and Siphonaptera. One clade, Pseudopolycentropodidae, from mid-Cretaceous Myanmar amber, contains Parapolycentropus. Here, we newly establish Dualula, assigned to Dualulidae, constituting the fifth lineage. Parapolycentropus and Dualula lineages are small, two-winged, with unique siphonate mouthparts for imbibing pollination drops. A cibarial pump provides siphonal food inflow; in Dualula, the siphon base surrounds a hypopharynx housing a small, valved pump constricted to a narrow salivary duct supplying outgoing enzymes for food fluidization. Indirect evidence links long-proboscid mouthpart structure with contemporaneous tubulate ovulate organs. Direct evidence of gymnospermous Cycadopites pollen is associated with one Parapolycentropus specimen. Parapolycentropus and Dualula exhibit hind-wing reduction that would precede haltere formation, likely caused by Ultrabithorax. Distinctive, male Aneuretopsychina genitalia are evident from specimens in copulo, supplemented by mixed-sex individuals of likely male mating swarms.


Assuntos
Evolução Biológica , Fósseis/anatomia & histologia , Herbivoria/fisiologia , Insetos/fisiologia , Âmbar , Animais , Cycadopsida , Feminino , Insetos/anatomia & histologia , Masculino , Mianmar , Filogenia , Pólen , Caracteres Sexuais
12.
J Morphol ; 280(5): 739-755, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30892750

RESUMO

Mengenillidae is a small, basal family of Strepsiptera, mainly characterized by free-living females in contrast to the endoparasitic females of Stylopidia. Here, we describe external and internal structures of the female abdomen of Eoxenos laboulbenei (Mengenillidae). The external morphology was examined and documented using microphotography. Internal structures were reconstructed three-dimensionally using a µCT-data set. The morphologically simplified abdomen comprises 10 segments. The integument is weakly sclerotized and flexible. Spiracles are present dorsolaterally on segments I-VII. Segment VII bears the posteroventral birth opening and the small abdominal segment X carries the anus at its apex. Numerous eggs float freely in the hemolymph. The musculature of segments I-IV is composed of ventral and dorsal longitudinal muscle bundles, strongly developed paramedial dorsoventral muscles and a complex meshwork of small pleural muscles, with minimal differences between the segments. Segments V-X contain more than 50 individual muscles, even though the musculature as a whole is weakly developed. Even though it is not involved in processing food, the digestive tract is well-developed. Its postabdominal section comprises a part of the midgut and the short hindgut. The midgut fills a large part of the postabdominal lumen. The lumina of the midgut and hindgut are not connected. Five or six nodular Malpighian tubules open into the digestive tract at the border region between the midgut and hindgut. The birth organ below the midgut releases the primary larvae after hatching via the birth opening at segment VII. It is likely derived from primary female genital ducts. The presence of six additional birth organs of segments I-VI are de novo formations and a groundplan apomorphy of Stylopidia, the large strepsipteran subgroup with endoparasitic females. The loss of the primary birth organ of segment VII is an apomorphy of Stylopiformia (Stylopidia excl. Corioxenidae).


Assuntos
Abdome/anatomia & histologia , Evolução Biológica , Genitália Feminina/anatomia & histologia , Insetos/anatomia & histologia , Exoesqueleto/anatomia & histologia , Animais , Sistema Digestório/anatomia & histologia , Feminino , Imageamento Tridimensional , Larva/anatomia & histologia , Túbulos de Malpighi/anatomia & histologia , Músculos/anatomia & histologia
13.
Arthropod Struct Dev ; 50: 1-14, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30731198

RESUMO

We present the first morphological study of the internal head structures of adults of the coniopterygid genus Aleuropteryx, which belong to the smallest known lacewings. The head is ventrally closed with a gula, which is unique in adult Neuroptera and otherwise developed in Megaloptera, the sister group of Neuroptera. The dorsal tentorial arms are directed posteriorly and fused, forming an arch that fulfills functions otherwise taken by the tentorial bridge. A newly found maxillary gland is present in both sexes. Several structural modifications correlated with miniaturization are recognized: a relative increase in the size of the brain, a reduction in the number of ommatidia and diameter of the facets, a countersunken cone-shaped ocular ridge, and a simplification of the tracheal system. The structure of the head differs strikingly from that of the previously studied species Coniopteryx pygmaea, indicating a greater variability in the family Coniopterygidae, which might be another effect of miniaturization.


Assuntos
Insetos/anatomia & histologia , Animais , Evolução Biológica , Feminino , Cabeça/anatomia & histologia , Insetos/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura
14.
J Morphol ; 280(4): 555-567, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30775799

RESUMO

Although the great genital diversity of the barklouse genus Trichadenotecnum has been described in previous studies, the specific function of the genital structures during the copulation process has received less investigative attention. We reconstructed 3D-models of each structure of the male and female genitalia of Trichadenotecnum incognitum in copula and those of uncopulated male and female of Trichadenotecnum pseudomedium. By comparing the changes in male and female genital structures and related muscles in copulated and uncopulated states, the function of each genital structure can be described. During the copulation, we found that the female subgenital plate was hooked into the male body by the distal process on the male paraproct and was fixed by the male epiproct, hypandrium and phallosome. In addition, sexual coevolution was suggested by tightly contacting structures, that is, thorny male hypandrium and thickened membrane around the female spermapore plate. These results not only give us a new understanding copulation process of Trichadenotecnum, but also explain the reasons why genital structures are so divers in the genus.


Assuntos
Genitália Feminina/anatomia & histologia , Genitália Feminina/diagnóstico por imagem , Genitália Masculina/anatomia & histologia , Genitália Masculina/diagnóstico por imagem , Insetos/anatomia & histologia , Microtomografia por Raio-X , Animais , Copulação/fisiologia , Feminino , Imageamento Tridimensional , Masculino , Movimento
15.
Pest Manag Sci ; 75(5): 1212-1222, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30306668

RESUMO

The midgut of insects is involved in digestion, osmoregulation and immunity. Although several defensive strategies are present in this organ, its organization and function may be disturbed by some insecticidal agents, including bioactive proteins like lectins and protease inhibitors (PIs) from plants. PIs interfere with digestion, leading to poor nutrient absorption and decreasing amino acid bioavailability. Intake of PIs can delay development, cause deformities and reduce fertility. Ingestion of PIs may lead to changes in the set of proteases secreted in the insect gut, but this response is often insufficient and results in aggravation of the malnutrition status. Lectins are proteins that are able to interact with glycoconjugates, including those linked to cell surfaces. Their effects on the midgut include disruption of the peritrophic matrix, brush border and secretory cell layer; induction of apoptosis and oxidative stress; interference with nutrient absorption and transport proteins; and damaging effects on symbionts. In addition, lectins can cross the intestinal barrier and reach the hemolymph. The establishment of resistant insect populations due to selective pressure resulting from massive use of a bioactive protein is an actual possibility, but this can be minimized by the multiple mode-of-action of these proteins, mainly the lectins. © 2018 Society of Chemical Industry.


Assuntos
Sistema Digestório/efeitos dos fármacos , Controle de Insetos/métodos , Insetos/anatomia & histologia , Lectinas/farmacologia , Plantas/química , Inibidores de Proteases/farmacologia , Adaptação Fisiológica/efeitos dos fármacos , Animais , Insetos/fisiologia
16.
Arthropod Struct Dev ; 48: 4-11, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30496889

RESUMO

Small arthropods are not simply scaled-down versions of their larger closest relatives, as changes in morphology and functional characters are largely governed by scaling laws. These same scaling laws set strict limits to size change toward smaller sizes. The evolution of extreme miniaturized forms involves the breaking of these constraints, by means of design innovations that allow evolutionary change to evade the limits posed by scaling laws. Here we review several cases studies in insects and other arthropods that illustrate this evolutionary path. We examine morphologies commonly recurring in miniaturized forms but not exclusive to them, morphologies exclusive to miniaturized forms and novel functional solutions supported by unconventional morphologies. We also discuss miniaturization and its evolvability taking into consideration arthropod postembryonic development and modular body organization. The modification of features commonly supposed not to change appears as a recurring pattern in arthropod miniaturization.


Assuntos
Insetos/anatomia & histologia , Animais , Evolução Biológica , Tamanho Corporal , Insetos/crescimento & desenvolvimento
17.
Arthropod Struct Dev ; 48: 49-55, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30500422

RESUMO

In this review the presently available morphological data on primary larvae of Strepsiptera are interpreted with respect to effects of miniaturization, but also their possible functional or phylogenetic background. The morphology of the 1st instars is mainly affected by functional constraints linked with parasitism but also by very distinct effects of miniaturization. The latter include modifications of the cephalic cuticle, the extremely limited free space in the body lumen, the shift of origins of cephalic muscles to the thorax, a reduced number of cephalic and thoracic muscles, extensions of muscles with cell bodies and other organelles, and an extreme concentration of the entire central nervous system in the middle region of the body. Pad-like adhesive structures on the distal leg segment and the abdominal jumping apparatus are clearly linked with the necessity to attach to a potential host but would not function in distinctly larger organisms.


Assuntos
Evolução Biológica , Insetos/anatomia & histologia , Larva/anatomia & histologia , Animais , Tamanho Corporal , Insetos/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Filogenia
18.
Biol Rev Camb Philos Soc ; 94(2): 555-574, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30259619

RESUMO

Hemipterans, mosquitoes, and parasitic wasps probe in a variety of substrates to find hosts for their larvae or food sources. Probes capable of sensing and precise steering enable insects to navigate through solid substrates without visual information and to reach targets that are hidden deep inside the substrate. The probes belong to non-related taxa and originate from abdominal structures (wasps) or mouthparts (hemipterans and mosquitoes), but nevertheless share several morphological characteristics. Although the transport function clearly differs (egg laying and acquisition of liquid food), the functional demands on the mechanical behaviour of the probe within the substrate tend to be similar. The probe needs to be thin to limit substrate deformation, and long, in order to attain substantial path lengths or depths. We linked the morphology across taxa to the different functional requirements, to provide insights into the biology of probing insects and the evolution of their probes. Current knowledge of insect probes is spread over many taxa, which offers the possibility to derive general characteristics of insect probing. Buckling during initial puncturing is limited by external support mechanisms. The probe itself consist of multiple (3-6) parts capable of sliding along one another. This multi-part construction presumably enables advancement and precise three-dimensional steering of the probe through the substrate with very low net external pushing forces, preventing buckling during substrate penetration. From a mechanical viewpoint, a minimum of three elements is required for 3D steering and volumetric exploration, as realised in the ovipositors of wasps. More elements, such as in six-element probes of mosquitoes, may enhance friction in soft substrates. Alternatively, additional elements can have functions other than 'drilling', such as saliva injection in mosquitoes. Despite the gross similarities, probes show differences in their cross sections, tip morphologies, relative lengths of their elements, and the shape of their interconnections. The hypothesis is that the probe morphology is influenced by the substrate properties, which are mostly unknown. Correlating the observed diversity to substrate-specific functional demands is therefore currently impossible. We conclude that a multipart probe with sliding elements is highly effective for volumetric substrate probing. Shared functional demands have led to an evolutionary convergence of slender multi-element probes in disparate insect taxa. To fully understand 3D probing, it is necessary to study the sensory and material properties, as well as the detailed kinematics and dynamics of the various probes in relation to the nature of the selective pressure originating from the species-specific substrates. Such knowledge will deepen our understanding of probing mechanisms and may support the development of slender, bio-inspired probes.


Assuntos
Insetos/anatomia & histologia , Insetos/fisiologia , Oviposição/fisiologia , Animais , Culicidae/anatomia & histologia , Culicidae/fisiologia , Hemípteros/anatomia & histologia , Hemípteros/fisiologia , Modelos Teóricos , Vespas/anatomia & histologia , Vespas/fisiologia
19.
Neotrop Entomol ; 48(3): 399-414, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30467704

RESUMO

During various studies of freshwater quality, twenty-four species of Smicridea were collected in Bolivia. This brings to thirty-one the number of Smicridea species present in this country. Four belong to the subgenus Smicridea Mclachlan J Linnean Soc London Zool 11: 98-141, 1871, which is recorded for the first time for the country. Additionally, 16 species in the subgenus Rhyacophylax Müller Zool Anzeiger 2: 38-40, 1879, are also registered for the first time. Three species are new and described from males: Smicridea (Rhyacophylax) molinai sp. nov., Smicridea (Rhyacophylax) ruedamartinae sp. nov., and Smicridea (Smicridea) moyai sp. nov.


Assuntos
Insetos/classificação , Animais , Bolívia , Insetos/anatomia & histologia , Masculino , Rios
20.
Insect Sci ; 26(5): 945-957, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29700985

RESUMO

Many extant insects have developed pad structures, euplantulae or arolia on their tarsi to increase friction or enhance adhesion for better mobility. Many polyneopteran insects with euplantulae, for example, Grylloblattodea, Mantophasmatodea and Orthoptera, have been described from the Mesozoic. However, the origin and evolution of stick insects' euplantulae are poorly understood due to rare fossil records. Here, we report the earliest fossil records of Timematodea hitherto, Tumefactipes prolongates gen. et sp. nov. and Granosicorpes lirates gen. et sp. nov., based on three specimens from mid-Cretaceous Burmese amber. Specimens of Tumefactipes prolongates gen. et sp. nov. have extremely specialized and expanded euplantulae on their tarsomere II. These new findings are the first known and the earliest fossil records about euplantula structure within Phasmatodea, demonstrating the diversity of euplantulae in Polyneoptera during the Mesozoic. Such tarsal pads might have increased friction and helped these mid-Cretaceous stick insects to climb more firmly on various surfaces, such as broad leaves, wetted tree branches or ground. These specimens provide more morphological data for us to understand the relationships of Timematodea, Euphasmatodea, Orthoptera and Embioptera, suggesting that Timematodea might be monophyletic with Euphasmatodea rather than Embioptera and Phasmatodea should have a closer relationship with Orthoptera rather than Embioptera.


Assuntos
Extremidades/anatomia & histologia , Fósseis/anatomia & histologia , Insetos/anatomia & histologia , Insetos/classificação , Âmbar , Animais , Feminino , Mianmar , Filogenia
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