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1.
Ecotoxicol Environ Saf ; 238: 113602, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35526455

RESUMO

The gut microbiota of insects plays a vital role in digestion, nutrient acquisition, metabolism of dietary toxins, pathogen immunity and maintenance of gut homeostasis. Bacillus thuringinensis (Bt) poisons target insects through its toxins that are activated in the insect gut. The effects of Bt toxins on gut microbiota of insects and their underlying mechanisms are not well understood. In this study, we found that Cry1Ab/2Ab toxins significantly changed the gut bacterial community's structure and reduced the total load of gut bacteria in the Locusta migratoria. In addition, Cry toxins significantly increased the level of reactive oxygen species (ROS) in the gut of locusts. Our results also showed that Cry1Ab/2Ab toxins induced the host gut's immune response by up-regulating of key genes in the Immune deficiency (IMD) and Toll pathway. RNA interference showed that knocking down Relish could narrow the difference in the load, diversity, and composition in gut bacteria caused by Cry toxins. Our findings suggest that Bt potentially influences the gut bacterial community of L. migratoria through host immune response.


Assuntos
Bacillus thuringiensis , Bacillus , Microbioma Gastrointestinal , Locusta migratoria , Animais , Bacillus thuringiensis/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/toxicidade , Endotoxinas/toxicidade , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/toxicidade , Imunidade , Insetos , Neópteros
2.
BMC Ecol Evol ; 22(1): 62, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35549660

RESUMO

BACKGROUND: The re-evolution of complex characters is generally considered impossible, yet, studies of recent years have provided several examples of phenotypic reversals shown to violate Dollo's law. Along these lines, the regain of wings in stick and leaf insects (Phasmatodea) was hypothesised to have occurred several times independently after an ancestral loss, a scenario controversially discussed among evolutionary biologists due to overestimation of the potential for trait reacquisition as well as to the lack of taxonomic data. RESULTS: We revisited the recovery of wings by reconstructing a phylogeny based on a comprehensive taxon sample of over 500 representative phasmatodean species to infer the evolutionary history of wings. We additionally explored the presence of ocelli, the photoreceptive organs used for flight stabilisation in winged insects, which might provide further information for interpreting flight evolution. Our findings support an ancestral loss of wings and that the ancestors of most major lineages were wingless. While the evolution of ocelli was estimated to be dependent on the presence of (fully-developed) wings, ocelli are nevertheless absent in the majority of all examined winged species and only appear in the members of few subordinate clades, albeit winged and volant taxa are found in every euphasmatodean lineage. CONCLUSION: In this study, we explored the evolutionary history of wings in Phasmatodea and demonstrate that the disjunct distribution of ocelli substantiates the hypothesis on their regain and thus on trait reacquisition in general. Evidence from the fossil record as well as future studies focussing on the underlying genetic mechanisms are needed to validate our findings and to further assess the evolutionary process of phenotypic reversals.


Assuntos
Insetos , Neópteros , Animais , Insetos/genética , Filogenia , Folhas de Planta , Asas de Animais
3.
Zootaxa ; 5093(2): 233-240, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35390809

RESUMO

A new species, Claassenia qingzanga Xiang, Huo Du, sp. nov. is described from Tibet and Qinghai Province of western China, this is the first record of Claassenia in Qinghai-Tibet Plateau. Males of the new species are brachypterous, the apex of the aedeagus with tiny spines dorsally and with dense protrusion laterally. The new species is compared to all regional Claassenia.


Assuntos
Insetos , Neópteros , Distribuição Animal , Animais , China , Masculino
4.
Zootaxa ; 5122(1): 1-80, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35391142

RESUMO

Paraphasma Redtenbacher, 1906 is a genus of fully-winged stick insects occurring in central and northern South America. We carried out a morphology-based taxonomic revision of this genus with emphasis on the phallic organ, a structure that has been poorly explored for taxonomic purposes in Phasmatodea. Additionally, pairwise genetic distances between mitochondrial COI gene sequences were calculated for ten Paraphasma specimens representing six species. We recognize nine valid species in the genus plus one nomen dubium, Paraphasma fasciatum Gray, 1835. We redescribe Paraphasma and the species previously assigned to it, describe Paraphasma indistinctum Chiquetto-Machado sp. nov., Paraphasma sooretama Chiquetto-Machado sp. nov. and Paraphasma spinicauda Chiquetto-Machado sp. nov., and provide a key to the species in the genus. The male of Paraphasma minus Redtenbacher, 1906 is described for the first time, as well as the eggs of six species. We transfer Paraphasma amabile Redtenbacher, 1906 to Pseudophasma Kirby, 1896 (comb. nov.) and synonymize Pseudophasma xanthotaenidium Gnther, 1930 under this species (syn. nov.). In addition, Phasma perspicillaris Stoll, 1813 is removed from the synonymy of Paraphasma laterale (Fabricius, 1775) and synonymized under Parastratocles xanthomela (Olivier, 1792) (syn. nov.). The examination of the phallic organ was essential for species delimitation, as most species of Paraphasma are very similar in the external morphology of both sexes. The analysis of the COI sequences supported the species delimitation, resulting in remarkably lower pairwise distances between conspecific individuals (p-distance 2.0%) than between different species (p-distance 6.917.5%). We hope that this paper will stimulate further studies exploring the taxonomic and phylogenetic potential of the internal male genitalia of stick insects.


Assuntos
Genes Mitocondriais , Neópteros , Animais , Feminino , Masculino , Filogenia
5.
Zootaxa ; 5120(2): 263-272, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35391170

RESUMO

A species of Phanoperla, P. wangi sp. nov., is described from Yunnan Province, China as new to science and compared with related species. Phanoperla himalayana Zwick, 1977, P. vietnamensis Zwick, 1986, and P. wieng Sivec Stark, 2010 are reported as new records from China.


Assuntos
Insetos , Neópteros , Distribuição Animal , Animais , China
6.
Arthropod Struct Dev ; 68: 101164, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35468454

RESUMO

The distal leg structures of Zoraptera are documented and discussed with respect to their functional morphology and evolutionary aspects. We investigated eight species using scanning electron microscopy. We analyzed material compositions of the tarsus in three representative species using confocal laser scanning microscopy. When possible, we included both sexes, wing morphs, and nymphs and compared the structures among them. The distal leg structure is unusually uniform across zorapterans regardless of the sex, morphs, and developmental stages. The observed features combine simplification with innovation. The former is likely partially correlated with cryptic microhabitats and miniaturization. Innovation includes a protibial cleaning organ. This is very likely an autapomorphy of Zoraptera. The tarsi are composed of two tarsomeres covered with setae. The pretarsus distally bears an unguitractor plate and well-sclerotized claws. The tarsomeres appear less-sclerotized than the covering setae. The articulation between the basitarsus and tarsomere 2 is hinge-like, implying that tarsomere 2 moves only mediolaterally. The simplified and specialized tarsal morphology is likely suitable for the typical zorapteran microhabitat, under bark. However, the irreversible complete loss of adhesive devices prevented zorapterans to make use of a broader spectrum of environments and was presumably one reason for the species paucity of the group.


Assuntos
Neópteros , Sensilas , Animais , Evolução Biológica , Feminino , Masculino , Microscopia Eletrônica de Varredura
7.
Int J Parasitol ; 52(8): 525-537, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35439499

RESUMO

Philopteridae feather lice are a group of ectoparasitic insects which have intimate relationships with their avian hosts. Feather lice include an enormous number of described species; however, the relationships of major lineages have been clouded by homoplasious characters due to convergent evolution. In this study, a comprehensive phylogenomic analysis of the group is performed which includes 137 feather louse species. Several other analyses are also completed including dating analysis, cophylogenetic reconstructions, and ancestral character estimation to understand the evolution of complex morphological and ecological traits. Phylogenetic results recover high support for the placement of major feather louse lineages, but with lower support for long-branched enigmatic genera found at the base of the tree. The results of dating analyses suggest modern feather lice began to diversify approximately 49 million years ago following the adaptive radiation of their avian hosts. Cost-based cophylogenetic reconstructions recover a high frequency of host switching, while congruence-based methods indicate a significant level of congruence between host and parasite trees. Ancestral state reconstructions favour a generalist ancestor and water bird host at the root. The analyses completed provide insight into the evolution of a diverse group of ectoparasitic insects which infest a wide variety of avian hosts. The results represent the most comprehensive phylogenetic hypothesis of the group to date and provide a framework for future classification of the family into natural groupings.


Assuntos
Interações Hospedeiro-Parasita , Ftirápteros , Animais , Aves/parasitologia , Neópteros , Ftirápteros/genética , Filogenia
8.
Zootaxa ; 5091(3): 477-486, 2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35391235

RESUMO

We describe and illustrate a new species of sucking louse, Hoplopleura tunneya new species, from the Australian pale field rat, Rattus tunneyi Thomas (Rodentia: Muridae). Currently, 22 species of the genus Hoplopleura Enderlein, 1904 (Phthiraptera: Anoplura: Hoplopleuridae) are known from Australian endemic rodents. Among the seven new endemic rodent species of the genus Rattus in Australia, R. tunneyi is one of five hosts to Hoplopleura lice. In addition, we give a list of all the species of Hoplopleura known from Australian endemic rodents. Including the introduced species Polyplax spinulosa, the total number of sucking louse species known from Australian endemic rodents is now 24.


Assuntos
Anoplura , Ftirápteros , Animais , Austrália/epidemiologia , Espécies Introduzidas , Muridae , Neópteros , Ratos , Roedores
9.
Zootaxa ; 5115(4): 559-570, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35391351

RESUMO

A new species of Zapada Ricker, 1952, Zapada kondratieffi sp. nov. from central Sichuan Province of China is described and illustrated, which represents the first record of the genus in China. The new species is characterized mainly by the presence of five simple cervical gills, vestigial inner paraproct lobe, and absence of paraproct spines. The preliminary molecular phylogenetic analysis using COI sequences recovered the relationship among eight species of Zapada and supports the close relationship between Z. kondratieffi and Zapada frigida (Claassen, 1923).


Assuntos
Insetos , Neópteros , Distribuição Animal , Animais , China , Filogenia
10.
Zootaxa ; 5115(2): 258-266, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35391370

RESUMO

Dracoleuctra siskiyou Lee Baumann gen. nov. sp. nov. a new apterous genus and species in the stonefly family Leuctridae (Insecta, Plecoptera), is described from males and females collected in southern Oregon, U.S.A. Habitus and terminalia are illustrated using both light photography images and scanning electron micrographs. Diagnostic characters, habitat, biological notes, and stonefly apterism in the Klamath Mountains region are discussed.


Assuntos
Insetos , Neópteros , Animais , Feminino , Masculino , Microscopia , Oregon
11.
Zootaxa ; 5094(1): 177-195, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35391456

RESUMO

Acroneuria Pictet, 1841 (Plecoptera: Perlidae) is a genus of stoneflies which presently includes 18 summer emerging Nearctic species. Diagnosis of species relies primarily on male aedeagal setal patterns, details of the ovum chorion, and larval dorsal maculations. Several species are morphologically cryptic in one or more life stages. In 2010, an apparently rare species, A. kosztarabi Kondratieff Kirchner, 1993, was petitioned for listing under the Endangered Species Act. A status survey conducted in 20162017 produced new specimen collections from near the type locality and surrounding areas. Examination of new material and the holotype of A. kirchneri Stark Kondratieff, 2004 demonstrates that it is a junior subjective synonym of A. kosztarabi. All life stages of A. kosztarabi are redescribed using color photographs and scanning electron microscope photomicrographs. Supporting data include maximum likelihood and pairwise genetic distance analyses based on mitochondrial cytochrome c oxidase subunit I fragment data. Acroneuria kosztarabi, previously known only from the type locality, is now reported from six states in the southeastern United States ranging from central North Carolina to western Tennessee and north to northern Virginia and northern Ohio.


Assuntos
Insetos , Neópteros , Animais , Masculino , Mitocôndrias
12.
Zootaxa ; 5093(5): 584-592, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35391465

RESUMO

A new species of the genus Suwallia Ricker, 1943, S. kuandian sp. nov., from Liaoning Province of northeastern China is described, illustrated, and compared with similar species. Suwallia asiatica Zhiltzova Levanidova, 1978 is reported for the first time from China. Additionally, Sweltsa illiesi Zhiltzova Levanidova, 1978 and the chloroperlid genus Alaskaperla Stewart DeWalt, 1991 are reported for the first time from China. The habitus and diagnostic features of these species are illustrated with color images.


Assuntos
Insetos , Neópteros , Distribuição Animal , Animais , China
13.
PLoS One ; 17(3): e0264264, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35239689

RESUMO

Among the Neotropical gripopterygids, the genus Paragripopteryx occurs along the Brazilian Atlantic coast to Uruguay. Since its first recognition by Enderlein in 1909, the genus underwent a confusing taxonomic history with some combinations. In this study, we aim to revise Paragripopteryx and present the first morphology-based phylogeny for the genus. The analysis comprised 38 morphological characters and their respective states in 30 terminal taxa, including 13 Paragripopteryx species, two new species identified as belonging to Paragripopteryx, and 15 outgroup species, among which we can highlight 12 different South American genera and one Australian genus of Gripopterygidae. The cladistic analysis yielded a parsimonious tree for k = 3 (137 steps, consistency index = 0.445, and retention index = 0.591) where most Paragripopteryx are nested, except for Uruguayan Paragripopteryx munoai. We can then infer that in its current circumscription Paragripopteryx is polyphyletic. The following two species are described: Paragripopteryx dasalmas sp. nov. and Paragripopteryx ogum sp. nov. Paragripopteryx baratinii is designated as a nomen dubium. Additionally, we provide a key for species identification, updated geographical records, and illustrations for all species. As a corollary, our study gathers relevant morphological information that can help to better understand this genus and create foundations for the next steps.


Assuntos
Insetos , Neópteros , Distribuição Animal , Animais , Austrália , Filogenia
14.
Sci Adv ; 8(8): eabg3842, 2022 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-35196080

RESUMO

The shift from sexual reproduction to parthenogenesis has occurred repeatedly in animals, but how the loss of sex affects genome evolution remains poorly understood. We generated reference genomes for five independently evolved parthenogenetic species in the stick insect genus Timema and their closest sexual relatives. Using these references and population genomic data, we show that parthenogenesis results in an extreme reduction of heterozygosity and often leads to genetically uniform populations. We also find evidence for less effective positive selection in parthenogenetic species, suggesting that sex is ubiquitous in natural populations because it facilitates fast rates of adaptation. Parthenogenetic species did not show increased transposable element (TE) accumulation, likely because there is little TE activity in the genus. By using replicated sexual-parthenogenetic comparisons, our study reveals how the absence of sex affects genome evolution in natural populations, providing empirical support for the negative consequences of parthenogenesis as predicted by theory.


Assuntos
Genoma de Inseto , Partenogênese , Animais , Elementos de DNA Transponíveis/genética , Insetos/genética , Neópteros/genética , Partenogênese/genética , Reprodução/genética
15.
Arthropod Struct Dev ; 66: 101141, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35114596

RESUMO

By using µCT technology, we reconstructed 3D models of the female genital structures and associated muscles of seven species from three suborders of Psocodea (free-living species only, formerly known as independent insect order "Psocoptera"). The homology of the female genital structures and associated muscles of different species is discussed. A total of 21 muscle groups were observed, and except for one muscle, all were homologized throughout the order. Moreover, some of the homologous muscles could be identified confidently in holometabolan insects. Using the muscles as landmarks, we discuss the homology of the ovipositor valves between Psocodea and other neopteran insects. Most importantly, the ovipositor of the suborder Trogiomorpha was identified to consist of the well-developed external valve (V3) plus a remnant of the dorsal valve (V2). We also examined the phylogenetic information included in the female genital muscles and found that certain muscles provide useful information and support deeper nodes (e.g., monophyly of the suborder Psocomorpha). The present study of female genital muscles not only helps us to better understand the phylogeny of Psocodea but also provides a solid foundation for research on muscle evolution.


Assuntos
Genitália Feminina/anatomia & histologia , Músculos/anatomia & histologia , Neópteros , Animais , Feminino , Neópteros/anatomia & histologia , Filogenia
16.
Mol Ecol ; 31(2): 467-481, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34704650

RESUMO

Understanding selection's impact on the genome is a major theme in biology. Functionally neutral genetic regions can be affected indirectly by natural selection, via their statistical association with genes under direct selection. The genomic extent of such indirect selection, particularly across loci not physically linked to those under direct selection, remains poorly understood, as does the time scale at which indirect selection occurs. Here, we use field experiments and genomic data in stick insects, deer mice and stickleback fish to show that widespread statistical associations with genes known to affect fitness cause many genetic loci across the genome to be impacted indirectly by selection. This includes regions physically distant from those directly under selection. Then, focusing on the stick insect system, we show that statistical associations between SNPs and other unknown, causal variants result in additional indirect selection in general and specifically within genomic regions of physically linked loci. This widespread indirect selection necessarily makes aspects of evolution more predictable. Thus, natural selection combines with chance genetic associations to affect genome-wide evolution across linked and unlinked loci and even in modest-sized populations. This process has implications for the application of evolutionary principles in basic and applied science.


Assuntos
Genoma , Seleção Genética , Animais , Genômica , Insetos/genética , Camundongos , Neópteros , Polimorfismo de Nucleotídeo Único
17.
Gene ; 808: 145974, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34592348

RESUMO

The mitochondrial genome (mitogenome) has been regarded as significant source of data to better understand the phylogenetic relationships within the Euphasmatodea, but no mitogenome in Aschiphasmatoidea has been sequenced to date. In this study, two mitogenomes of Orthomeria smaragdinum and Nanhuaphasma hamicercum of Aschiphasmatidae were sequenced and annotated for the first time. The same mitochondrial gene rearrangement structure was present in the two mitogenomes sequenced, showing as the translocation of tRNA-Arg and tRNA-Asn, which conformed to the tandem duplication-random loss and could be used as a possible synapomorphy for Aschiphasmatidae. The phylogenetic results based on the maximum likelihood (ML) and bayesian inference (BI) methods both showed that Aschiphasmatidae and Neophasmatodea in Euphasmatodea are sister taxa. Although the monophyly of Oriophasmata, Occidophasmata, Diapheromeridae, Phasmatidae, Lonchodidae and Bacilloidea has not been solved, the monophyly of Neophasmatodea and Phyllioidea was well supported.


Assuntos
Genoma Mitocondrial/genética , Mitocôndrias/genética , Nematoides/genética , Animais , Sequência de Bases/genética , Ordem dos Genes/genética , Rearranjo Gênico/genética , Genômica/métodos , Neópteros/genética , Filogenia
18.
Zootaxa ; 5016(4): 543-558, 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34810431

RESUMO

A complementary re-description of Kyphopteryx dorsalis Kimmins, 1947 is presented on the basis of a fresh male and additional females from southeastern Tibet, southwestern China. The hitherto unknown inner structures of the female terminalia are described, as well as further details of the male genitalia. In this study, we also present the first records of Capnia s.l. yunnana Li Yang, 2011 from Tibet and a formal description of an unassociated Capnia s.l. female collected together with the above species. An updated checklist of the named species of Capniidae and Taeniopterygidae from China is also given.


Assuntos
Hemípteros , Insetos , Distribuição Animal , Animais , China , Feminino , Masculino , Neópteros
19.
Zootaxa ; 4996(2): 343-352, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34810526

RESUMO

A new genus of family Perlodidae, Tibetisoperla Huo Du, gen. nov. is described with one new species from Tibet, China. Male of the new genus is characterized by the divided tergum 10 with several large apical erect setae, highly reduced vesicle on sternum 8, and the sclerotized paraprocts with separate apical sclerite.


Assuntos
Insetos , Neópteros , Distribuição Animal , Animais , China , Masculino , Tibet
20.
Zootaxa ; 5061(3): 573-583, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34810607

RESUMO

Microperla retroloba (Wu, 1937) is a poorly described species from Gansu Province of China and the types of which were apparently lost. Herein, a neotype of M. retroloba is designated based on new material from Ningxia Hui Autonomous Region adjacent to Gansu Province. Male, female, larva and egg morphology of M. retroloba are described, illustrated and compared with all congeners.


Assuntos
Neópteros , Animais , Feminino , Larva , Masculino
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