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1.
Cladistics ; 40(1): 21-33, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37787424

RESUMO

The owlet moths (Noctuoidea; ~43-45K described species) are one of the most ecologically diverse and speciose superfamilies of animals. Moreover, they comprise some of the world's most notorious pests of agriculture and forestry. Despite their contributions to terrestrial biodiversity and impacts on ecosystems and economies, the evolutionary history of Noctuoidea remains unclear because the superfamily lacks a statistically robust phylogenetic and temporal framework. We reconstructed the phylogeny of Noctuoidea using data from 1234 genes (946.4 kb nucleotides) obtained from the genome and transcriptome sequences of 76 species. The relationships among the six families of Noctuoidea were well resolved and consistently recovered based on both concatenation and gene coalescence approaches, supporting the following relationships: Oenosandridae + (Notodontidae + (Erebidae + (Nolidae + (Euteliidae + Noctuidae)))). A Yule tree prior with three unlinked molecular clocks was identified as the preferred BEAST analysis using marginal-likelihood estimations. The crown age of Noctuoidea was estimated at 74.5 Ma, with most families originating before the end of the Paleogene (23 Ma). Our study provides the first statistically robust phylogenetic and temporal framework for Noctuoidea, including all families of owlet moths, based on large-scale genomic data.


Assuntos
Genoma Mitocondrial , Mariposas , Animais , Filogenia , Ecossistema , Mariposas/genética , Genômica
2.
PeerJ ; 11: e16049, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965290

RESUMO

We critically re-examine 17 records of fossils currently assigned to the lepidopteran superfamily Bombycoidea, which includes the silk moths, emperor moths and hawk moths. These records include subfossils, compression and impression fossils, permineralizations and ichnofossils. We assess whether observable morphological features warrant their confident assignment to the superfamily. None of the examined fossils displays characters that allow unequivocal identification as Sphingidae, but three fossils and a subfossil (Mioclanis shanwangiana Zhang, Sun and Zhang, 1994, two fossil larvae, and a proboscis in asphaltum) have combinations of diagnostic features that support placement in the family. The identification of a fossil pupa as Bunaeini (Saturniidae) is well supported. The other fossils that we evaluate lack definitive bombycoid and, in several cases, even lepidopteran characters. Some of these dubious fossils have been used as calibration points in earlier studies casting doubt on the resulting age estimates. All fossil specimens reliably assigned to Bombycoidea are relatively young, the earliest fossil evidence of the superfamily dating to the middle Miocene.


Assuntos
Manduca , Mariposas , Animais , Fósseis , Filogenia , Larva
3.
Proc Biol Sci ; 290(2008): 20231385, 2023 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-37788699

RESUMO

Weevils have been shown to play significant roles in the obligate pollination of Australian cycads. In this study, we apply museomics to produce a first molecular phylogeny estimate of the Australian cycad weevils, allowing an assessment of their monophyly, placement and relationships. Divergence dating suggests that the Australian cycad weevils originated from the Late Oligocene to the Middle Miocene and that the main radiation of the cycad-pollinating groups occurred from the Middle to the Late Miocene, which is congruent with the diversification of the Australian cycads, thus refuting any notion of an ancient ciophilous system in Australia. Taxonomic studies reveal the existence of 19 Australian cycad weevil species and that their associations with their hosts are mostly non-species-specific. Co-speciation analysis shows no extensive co-speciation events having occurred in the ciophilous system of Australian cycads. The distribution pattern suggests that geographical factors, rather than diversifying coevolution, constitute the overriding process shaping the Australian cycad weevil diversity. The synchronous radiation of cycads and weevil pollinators is suggested to be a result of the post-Oligocene diversification common in Australian organisms.


Assuntos
Gorgulhos , Animais , Gorgulhos/genética , Austrália , Filogenia , Cycadopsida , Geografia
4.
Zootaxa ; 5316(1): 1-194, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37518401

RESUMO

Adults of the African species of the genus Neoperla Needham, 1905 (Plecoptera: Perlidae: Perlinae) are revised, and 82 valid species are recognised. Of the original 29 named species, 14 valid ones are redescribed from types, nine lectotypes are designated, and nine new synonymies are proposed. Sixty-two new species are named, and several additional new species only known from material insufficient for formal description are listed. There are one unavailable nomen nudum and three doubtful names. Diagnostic morphological traits of the recognised species are described and illustrated in detail where available of males, females, and eggs. Dichotomous keys to all species are provided. Mitochondrial DNA-data of 71 species-group taxa are available, which permits reliable association of sexes and minimises the risk of synonymies between species known from only one sex. Importantly, this includes DNA sequences from 50 holotypes. The DNA-data will also permit future monitoring with eDNA sequencing and identification of nymphs, which are probably important but so far unidentifiable bioindicators in streams. The genus Neoperla occurs largely in the northern hemisphere and in Africa, where it is restricted to the Ethiopian region south of the Sahara but unknown from Madagascar. A single specimen not clearly distinct from a widespread mainland species was taken on Comoro Island. All African species are endemic, but one African species group has a few outlying members in Asia. The Asian N. montivaga-group is not known from Africa. The following new species are described and named: N. aethiopica n. sp., N. amoena n. sp., N. angolana n. sp., N. bareensis n. sp., N. bella n. sp., N. benti n. sp., N. beta n. sp., N. bipolaris n. sp., N. biserrata n. sp., N. brachyphallus n. sp., N. caeleps n. sp., N. cataractae n. sp., N. claviger n. sp., N. coffea n. sp., N. costata n. sp., N. crenulata n. sp., N. crustata n. sp., N. decorata n. sp., N. dianae n. sp., N. dolium n. sp., N. dundoana n. sp., N. duodeviginti n. sp., N. erinaceus n. sp., N. excavata n. sp., N. filamentosa n. sp., N. funiculata n. sp., N. gibbosa n. sp., N. gordius n. sp., N. heideae n. sp., N. ivanloebli n. sp., N. juxtadidita n. sp., N. kalengonis n. sp., N. larvata n. sp., N. lineata n. sp., N. luhohonis n. sp., N. massevensis n. sp., N. multiserrata n. sp., N. muyukae n. sp., N. nichollsi n. sp., N. occulta n. sp., N. orthonema n. sp., N. pallidogigas n. sp., N. panafricana n. sp., N. pickeri n. sp., N. pilulifera n. sp., N. pirus n. sp., N. planidorsum n. sp., N. plicata n. sp., N. proxima n. sp., N. pusilla n. sp., N. rostrata n. sp., N. sambarua n. sp., N. sassandrae n. sp., N. schuelei n. sp., N. serrula n. sp., N. simplex n. sp., N. socia n. sp., N. sorella n. sp., N. spaghetti n. sp., N. spectabilis n. sp., N. spironema n. sp., N. tangana n. sp., N. tansanica n. sp., N. usambara n. sp., and N. vicina n. sp..


Assuntos
Insetos , Neópteros , Feminino , Masculino , Animais , Distribuição Animal
5.
Mol Ecol ; 32(23): 6377-6393, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36065738

RESUMO

Alpine plant-pollinator communities play an important role in the functioning of alpine ecosystems, which are highly threatened by climate change. However, we still have a poor understanding of how environmental factors and spatiotemporal variability shape these communities. Here, we investigate what drives structure and beta diversity in a plant-pollinator metacommunity from the Australian alpine region using two approaches: pollen DNA metabarcoding (MB) and observations. Individual pollinators often carry pollen from multiple plant species, and therefore we expected MB to reveal a more diverse and complex network structure. We used two gene regions (ITS2 and trnL) to identify plant species present in the pollen loads of 154 insect pollinator specimens from three alpine habitats and construct MB networks, and compared them to networks based on observations alone. We compared species and interaction turnover across space for both types of networks, and evaluated their differences for plant phylogenetic diversity and beta diversity. We found significant structural differences between the two types of networks; notably, MB networks were much less specialized but more diverse than observation networks, with MB detecting many cryptic plant species. Both approaches revealed that alpine pollination networks are very generalized, but we estimated a high spatial turnover of plant species (0.79) and interaction rewiring (0.6) as well as high plant phylogenetic diversity (0.68) driven by habitat differences based on the larger diversity of plant species and species interactions detected with MB. Overall, our findings show that habitat and microclimatic heterogeneity drives diversity and fine-scale spatial turnover of alpine plant-pollinator networks.


Assuntos
Código de Barras de DNA Taxonômico , Ecossistema , Animais , Filogenia , Austrália , Pólen/genética , Plantas/genética , Polinização/genética , Flores , Insetos/genética
6.
Mol Phylogenet Evol ; 172: 107486, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35469917

RESUMO

Cerambycinae is the second-largest subfamily of longhorn beetles in the Southern Hemisphere. The phylogeny of Cerambycinae is poorly known, resulting in a highly artificial tribal-level classification and a largely speculative evolutionary history. We reconstructed the phylogenetic relationships of Cerambycinae at the generic level using anchored hybrid enrichment data from hundreds of nuclear genes, with a primary focus on the extraordinarily diverse faunas of Australia and New Zealand. We also estimated divergence times by incorporating fossil calibrations in our analyses. We identified two main clades within Cerambycinae, which can also be separated morphologically by a distinct type of antennal foramen. We recovered a Late Jurassic origin of crown Cerambycinae. Dorcasominae, which was newly found to have representatives in Australia, was notably derived from within Cerambycinae. We recovered two independent origins of Australian Cerambycinae: one clade originated in the Early Cretaceous and is likely endemic to the Southern Hemisphere, while the other clade appears to have immigrated to Australia, perhaps from the Northern Hemisphere. Within the Australian lineages were multiple independent origins of New Zealand taxa, all of which are relative host-plant generalists. Tribal relationships and assignments are discussed, and based on our results, the following major nomenclatural acts were made: Dorcasominae Lacordaire, 1868 is downgraded to a tribe Dorcasomini of Cerambycinae Latreille, 1804; Neostenini Lacordaire, 1868 syn. nov. is treated as a junior synonym of Uracanthini Blanchard, 1851.


Assuntos
Besouros , Animais , Austrália , Fósseis , Nova Zelândia , Filogenia
7.
Cladistics ; 38(3): 277-300, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34710244

RESUMO

Gracillariidae is the most taxonomically diverse cosmopolitan leaf-mining moth family, consisting of nearly 2000 named species in 105 described genera, classified into eight extant subfamilies. The majority of gracillariid species are internal plant feeders as larvae, creating mines and galls in plant tissue. Despite their diversity and ecological adaptations, their phylogenetic relationships, especially among subfamilies, remain uncertain. Genomic data (83 taxa, 589 loci) were integrated with Sanger data (130 taxa, 22 loci), to reconstruct a phylogeny of Gracillariidae. Based on analyses of both datasets combined and analyzed separately, monophyly of Gracillariidae and all its subfamilies, monophyly of the clade "LAMPO" (subfamilies: Lithocolletinae, Acrocercopinae, Marmarinae, Phyllocnistinae, and Oecophyllembiinae) and relationships of its subclade "AMO" (subfamilies: Acrocercopinae, Marmarinae, and Oecophyllembiinae) were strongly supported. A sister-group relationship of Ornixolinae to the remainder of the family, and a monophyletic leaf roller lineage (Callicercops Vári + Parornichinae) + Gracillariinae, as sister to the "LAMPO" clade were supported by the most likely tree. Dating analyses indicate a mid-Cretaceous (105.3 Ma) origin of the family, followed by a rapid diversification into the nine subfamilies predating the Cretaceous-Palaeogene extinction. We hypothesize that advanced larval behaviours, such as making keeled or tentiform blotch mines, rolling leaves and galling, allowed gracillariids to better avoid larval parasitoids allowing them to further diversify. Finally, we stabilize the classification by formally re-establishing the subfamily ranks of Marmarinae stat.rev., Oecophyllembiinae stat.rev. and Parornichinae stat.rev., and erect a new subfamily, Callicercopinae Li, Ohshima and Kawahara to accommodate the enigmatic genus Callicercops.


Assuntos
Mariposas , Animais , Larva/genética , Mariposas/genética , Filogenia
8.
PLoS One ; 16(9): e0256861, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34534224

RESUMO

Transcriptome-based exon capture approaches, along with next-generation sequencing, are allowing for the rapid and cost-effective production of extensive and informative phylogenomic datasets from non-model organisms for phylogenetics and population genetics research. These approaches generally employ a reference genome to infer the intron-exon structure of targeted loci and preferentially select longer exons. However, in the absence of an existing and well-annotated genome, we applied this exon capture method directly, without initially identifying intron-exon boundaries for bait design, to a group of highly diverse Haloniscus (Philosciidae), paraplatyarthrid and armadillid isopods, and examined the performance of our methods and bait design for phylogenetic inference. Here, we identified an isopod-specific set of single-copy protein-coding loci, and a custom bait design to capture targeted regions from 469 genes, and analysed the resulting sequence data with a mapping approach and newly-created post-processing scripts. We effectively recovered a large and informative dataset comprising both short (<100 bp) and longer (>300 bp) exons, with high uniformity in sequencing depth. We were also able to successfully capture exon data from up to 16-year-old museum specimens along with more distantly related outgroup taxa, and efficiently pool multiple samples prior to capture. Our well-resolved phylogenies highlight the overall utility of this methodological approach and custom bait design, which offer enormous potential for application to future isopod, as well as broader crustacean, molecular studies.


Assuntos
Proteínas de Artrópodes/genética , Éxons , Genoma , Isópodes/genética , Fases de Leitura Aberta , Animais , Proteínas de Artrópodes/classificação , Proteínas de Artrópodes/metabolismo , Conjuntos de Dados como Assunto , Expressão Gênica , Loci Gênicos , Genética Populacional , Sequenciamento de Nucleotídeos em Larga Escala , Íntrons , Isópodes/classificação , Filogenia
9.
Cladistics ; 37(3): 276-297, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34478201

RESUMO

Bombyliidae is a very species-rich and widespread family of parasitoid flies with more than 250 genera classified into 17 extant subfamilies. However, little is known about their evolutionary history or how their present-day diversity was shaped. Transcriptomes of 15 species and anchored hybrid enrichment (AHE) sequence captures of 86 species, representing 94 bee fly species and 14 subfamilies, were used to reconstruct the phylogeny of Bombyliidae. We integrated data from transcriptomes across each of the main lineages in our AHE tree to build a data set with more genes (550 loci versus 216 loci) and higher support levels. Our overall results show strong congruence with the current classification of the family, with 11 out of 14 included subfamilies recovered as monophyletic. Heterotropinae and Mythicomyiinae are successive sister groups to the remainder of the family. We examined the evolution of key morphological characters through our phylogenetic hypotheses and show that neither the "sand chamber subfamilies" nor the "Tomophthalmae" are monophyletic in our phylogenomic analyses. Based on our results, we reinstate two tribes at the subfamily level (Phthiriinae stat. rev. and Ecliminae stat. rev.) and we include the genus Sericosoma Macquart (previously incertae sedis) in the subfamily Oniromyiinae, bringing the total number of bee fly subfamilies to 19. Our dating analyses indicate a Jurassic origin of the family (165-194 Ma), with the sand chamber evolving early in bee fly evolution, in the late Jurassic or mid-Cretaceous (100-165 Ma). We hypothesize that the angiosperm radiation and the hothouse climate established during the late Cretaceous accelerated the diversification of bee flies, by providing an expanded range of resources for the parasitoid larvae and nectarivorous adults.


Assuntos
Abelhas/classificação , Biodiversidade , Evolução Molecular , Larva/fisiologia , Filogenia , Transcriptoma , Animais , Abelhas/genética , Abelhas/fisiologia , Larva/genética , Análise de Sequência de DNA
10.
BMC Biol ; 19(1): 7, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-33446206

RESUMO

BACKGROUND: Horizontal gene transfer (HGT) has been documented in many herbivorous insects, conferring the ability to digest plant material and promoting their remarkable ecological diversification. Previous reports suggest HGT of antibacterial enzymes may have contributed to the insect immune response and limit bacterial growth. Carnivorous insects also display many evolutionary successful lineages, but in contrast to the plant feeders, the potential role of HGTs has been less well-studied. RESULTS: Using genomic and transcriptomic data from 38 species of ladybird beetles, we identified a set of bacterial cell wall hydrolase (cwh) genes acquired by this group of beetles. Infection with Bacillus subtilis led to upregulated expression of these ladybird cwh genes, and their recombinantly produced proteins limited bacterial proliferation. Moreover, RNAi-mediated cwh knockdown led to downregulation of other antibacterial genes, indicating a role in antibacterial immune defense. cwh genes are rare in eukaryotes, but have been maintained in all tested Coccinellinae species, suggesting that this putative immune-related HGT event played a role in the evolution of this speciose subfamily of predominant predatory ladybirds. CONCLUSION: Our work demonstrates that, in a manner analogous to HGT-facilitated plant feeding, enhanced immunity through HGT might have played a key role in the prey adaptation and niche expansion that promoted the diversification of carnivorous beetle lineages. We believe that this represents the first example of immune-related HGT in carnivorous insects with an association with a subsequent successful species radiation.


Assuntos
Antibiose/genética , Evolução Biológica , Besouros/genética , Transferência Genética Horizontal , Genes Bacterianos , Genes de Insetos , Adaptação Biológica , Animais , Parede Celular/química , Parede Celular/enzimologia , Besouros/enzimologia , Interações Hospedeiro-Patógeno , Hidrolases/genética
11.
Proc Natl Acad Sci U S A ; 116(45): 22657-22663, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31636187

RESUMO

Butterflies and moths (Lepidoptera) are one of the major superradiations of insects, comprising nearly 160,000 described extant species. As herbivores, pollinators, and prey, Lepidoptera play a fundamental role in almost every terrestrial ecosystem. Lepidoptera are also indicators of environmental change and serve as models for research on mimicry and genetics. They have been central to the development of coevolutionary hypotheses, such as butterflies with flowering plants and moths' evolutionary arms race with echolocating bats. However, these hypotheses have not been rigorously tested, because a robust lepidopteran phylogeny and timing of evolutionary novelties are lacking. To address these issues, we inferred a comprehensive phylogeny of Lepidoptera, using the largest dataset assembled for the order (2,098 orthologous protein-coding genes from transcriptomes of 186 species, representing nearly all superfamilies), and dated it with carefully evaluated synapomorphy-based fossils. The oldest members of the Lepidoptera crown group appeared in the Late Carboniferous (∼300 Ma) and fed on nonvascular land plants. Lepidoptera evolved the tube-like proboscis in the Middle Triassic (∼241 Ma), which allowed them to acquire nectar from flowering plants. This morphological innovation, along with other traits, likely promoted the extraordinary diversification of superfamily-level lepidopteran crown groups. The ancestor of butterflies was likely nocturnal, and our results indicate that butterflies became day-flying in the Late Cretaceous (∼98 Ma). Moth hearing organs arose multiple times before the evolutionary arms race between moths and bats, perhaps initially detecting a wide range of sound frequencies before being co-opted to specifically detect bat sonar. Our study provides an essential framework for future comparative studies on butterfly and moth evolution.


Assuntos
Borboletas/genética , Evolução Molecular , Mariposas/genética , Filogenia , Animais , Borboletas/classificação , Borboletas/fisiologia , Mariposas/classificação , Mariposas/fisiologia
12.
Ecol Evol ; 9(5): 2933-2944, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30891227

RESUMO

Five species of noctuid moths, Helicoverpa armigera, H. punctigera, H. assulta, H. zea, and H. gelotopoeon, are major agricultural pests inhabiting various and often overlapping global distributions. Visual identification of these species requires a great deal of expertise and misidentification can have repercussions for pest management and agricultural biosecurity. Here, we report on the complete mitochondrial genomes of H. assulta assulta and H. assulta afra, H. gelotopoeon, H. punctigera, H. zea, and H. armigera armigera and H. armigera conferta' assembled from high-throughput sequencing data. This study significantly increases the mitogenome resources for these five agricultural pests with sequences assembled from across different continents, including an H. armigera individual collected from an invasive population in Brazil. We infer the phylogenetic relationships of these five Helicoverpa species based on the 13 mitochondrial DNA protein-coding genes (PCG's) and show that two publicly available mitogenomes of H. assulta (KP015198 and KR149448) have been misidentified or incorrectly assembled. We further consolidate existing PCR-RFLP methods to cover all five Helicoverpa pest species, providing an updated method that will contribute to species differentiation and to future monitoring efforts of Helicoverpa pest species across different continents. We discuss the value of Helicoverpa mitogenomes to assist with species identification in view of the context of the rapid spread of H. armigera in the New World. With this work, we provide the molecular resources necessary for future studies of the evolutionary history and ecology of these species.

13.
Proc Natl Acad Sci U S A ; 115(19): 5034-5039, 2018 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-29610329

RESUMO

Within the mega-pest lineage of heliothine moths are a number of polyphagous, highly mobile species for which the exchange of adaptive traits through hybridization would affect their properties as pests. The recent invasion of South America by one of the most significant agricultural pests, Helicoverpa armigera, raises concerns for the formation of novel combinations of adaptive genes following hybridization with the closely related Helicoverpa zea To investigate the propensity for hybridization within the genus Helicoverpa, we carried out whole-genome resequencing of samples from six species, focusing in particular upon H. armigera population structure and its relationship with H. zea We show that both H. armigera subspecies have greater genetic diversity and effective population sizes than do the other species. We find no signals for gene flow among the six species, other than between H. armigera and H. zea, with nine Brazilian individuals proving to be hybrids of those two species. Eight had largely H. armigera genomes with some introgressed DNA from H. zea scattered throughout. The ninth resembled an F1 hybrid but with stretches of homozygosity for each parental species that reflect previous hybridization. Regions homozygous for H. armigera-derived DNA in this individual included one containing a gustatory receptor and esterase genes previously associated with host range, while another encoded a cytochrome P450 that confers insecticide resistance. Our data point toward the emergence of novel hybrid ecotypes and highlight the importance of monitoring H. armigera genotypes as they spread through the Americas.


Assuntos
Quimera/genética , Fluxo Gênico , Genoma de Inseto , Proteínas de Insetos/genética , Resistência a Inseticidas/genética , Mariposas/genética , Animais , Especificidade da Espécie
14.
Biodivers Data J ; (6): e22236, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29674935

RESUMO

BACKGROUND: Bombycoidea is an ecologically diverse and speciose superfamily of Lepidoptera. The superfamily includes many model organisms, but the taxonomy and classification of the superfamily has remained largely in disarray. Here we present a global checklist of Bombycoidea. Following Zwick (2008) and Zwick et al. (2011), ten families are recognized: Anthelidae, Apatelodidae, Bombycidae, Brahmaeidae, Carthaeidae, Endromidae, Eupterotidae, Phiditiidae, Saturniidae and Sphingidae. The former families Lemoniidae and Mirinidae are included within Brahmaeidae and Endromidae respectively. The former bombycid subfamilies Oberthueriinae and Prismostictinae are also treated as synonyms of Endromidae, and the former bombycine subfamilies Apatelodinae and Phitditiinae are treated as families. NEW INFORMATION: This checklist represents the first effort to synthesize the current taxonomic treatment of the entire superfamily. It includes 12,159 names and references to their authors, and it accounts for the recent burst in species and subspecies descriptions within family Saturniidae (ca. 1,500 within the past 10 years) and to a lesser extent in Sphingidae (ca. 250 species over the same period). The changes to the higher classification of Saturniidae proposed by Nässig et al. (2015) are rejected as premature and unnecessary. The new tribes, subtribes and genera described by Cooper (2002) are here treated as junior synonyms. We also present a new higher classification of Sphingidae, based on Kawahara et al. (2009), Barber and Kawahara (2013) and a more recent phylogenomic study by Breinholt et al. (2017), as well as a reviewed genus and species level classification, as documented by Kitching (2018).

15.
Curr Biol ; 27(20): 3157-3161.e4, 2017 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-28988864

RESUMO

The Lord Howe Island stick insect, Dryococelus australis, was once common on the island but was driven to extinction after the arrival of ship rats in the early 20th century [1, 2]. It was thought to be extinct for decades, until a tiny population of similar-looking stick insects was discovered 20 km away, on the islet of Ball's Pyramid, in 2001 [2]. Individuals from this population are currently being reared in Australia and elsewhere in the world, with the eventual goal of recolonizing Lord Howe Island [3]. Recent surveys of the wild population on Ball's Pyramid suggest that it is among the world's rarest species. However, there are significant morphological differences between Ball's Pyramid and museum specimens, and there has never been a genetic confirmation of the rediscovered population's species identity. Because Dryococelus is monotypic, there are also no known extant relatives for comparison. Using shotgun genomic data from the Ball's Pyramid population, we assembled a draft genome and the complete mitochondrial genome. We found that the genome is massive, over 4 Gb in size, and is most likely hexaploid. We re-sequenced mitochondrial genomes from historic museum specimens collected on Lord Howe Island before the extinction event. Sequence divergence between the two populations is less than 1% and is within the range of intraspecific differences between the museum specimens, suggesting that they are conspecific and that D. australis has successfully evaded extinction so far. This work highlights the importance of museum collections for taxonomic validation in the context of ongoing conservation efforts.


Assuntos
Extinção Biológica , Genoma de Inseto , Genoma Mitocondrial , Insetos/genética , Animais , Conservação dos Recursos Naturais , Ilhas , Museus , New South Wales , Oceano Pacífico
16.
BMC Evol Biol ; 17(1): 151, 2017 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-28651535

RESUMO

BACKGROUND: The tribe Coccinellini is a group of relatively large ladybird beetles that exhibits remarkable morphological and biological diversity. Many species are aphidophagous, feeding as larvae and adults on aphids, but some species also feed on other hemipterous insects (i.e., heteropterans, psyllids, whiteflies), beetle and moth larvae, pollen, fungal spores, and even plant tissue. Several species are biological control agents or widespread invasive species (e.g., Harmonia axyridis (Pallas)). Despite the ecological importance of this tribe, relatively little is known about the phylogenetic relationships within it. The generic concepts within the tribe Coccinellini are unstable and do not reflect a natural classification, being largely based on regional revisions. This impedes the phylogenetic study of important traits of Coccinellidae at a global scale (e.g. the evolution of food preferences and biogeography). RESULTS: We present the most comprehensive phylogenetic analysis of Coccinellini to date, based on three nuclear and one mitochondrial gene sequences of 38 taxa, which represent all major Coccinellini lineages. The phylogenetic reconstruction supports the monophyly of Coccinellini and its sister group relationship to Chilocorini. Within Coccinellini, three major clades were recovered that do not correspond to any previously recognised divisions, questioning the traditional differentiation between Halyziini, Discotomini, Tytthaspidini, and Singhikaliini. Ancestral state reconstructions of food preferences and morphological characters support the idea of aphidophagy being the ancestral state in Coccinellini. This indicates a transition from putative obligate scale feeders, as seen in the closely related Chilocorini, to more agile general predators. CONCLUSIONS: Our results suggest that the classification of Coccinellini has been misled by convergence in morphological traits. The evolutionary history of Coccinellini has been very dynamic in respect to changes in host preferences, involving multiple independent host switches from different insect orders to fungal spores and plants tissues. General predation on ephemeral aphids might have created an opportunity to easily adapt to mixed or specialised diets (e.g. obligate mycophagy, herbivory, predation on various hemipteroids or larvae of leaf beetles (Chrysomelidae)). The generally long-lived adults of Coccinellini can consume pollen and floral nectars, thereby surviving periods of low prey frequency. This capacity might have played a central role in the diversification history of Coccinellini.


Assuntos
Besouros/classificação , Besouros/genética , Animais , Evolução Biológica , Besouros/crescimento & desenvolvimento , Besouros/fisiologia , Evolução Molecular , Preferências Alimentares , Espécies Introduzidas , Larva/fisiologia , Filogenia , Comportamento Predatório
17.
Cladistics ; 33(5): 449-466, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34724755

RESUMO

Tectonic dynamics and niche availability play intertwined roles in determining patterns of diversification. Such drivers explain the current distribution of many clades, whereas events such as the rise of angiosperms can have more specific impacts, such as on the diversification rates of herbivores. The Tortricidae, a diverse group of phytophagous moths, are ideal for testing the effects of these determinants on the diversification of herbivorous clades. To estimate ancestral areas and diversification patterns in Tortricidae, a complete tribal-level dated tree was inferred using molecular markers (one mitochondrial and five nuclear) and calibrated using fossil constraints. We found that Tortricidae diverged from their sister group c. 120 Myr ago (Ma) and diversified c. 97 Ma, a timeframe synchronous with the rise of angiosperms in the Early-mid Cretaceous. Ancestral areas analysis, based on updated Wallace's biogeographical regions, supports the hypothesis of a Gondwanan origin of Tortricidae in the South American plate. We also detected an increase in speciation rate that coincided with the peak of angiosperm diversification in the Cretaceous. This in turn probably was further heightened by continental colonization of the Palaeotropics when angiosperms became dominant by the end of the Late Cretaceous.

18.
Curr Opin Insect Sci ; 18: 83-88, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27939715

RESUMO

Museums and herbaria represent vast repositories of biological material. Until recently, working with these collections has been difficult, due to the poor condition of historical DNA. However, recent advances in next-generation sequencing technology, and subsequent development of techniques for preparing and sequencing historical DNA, have recently made working with collection specimens an attractive option. Here we describe the unique technical challenges of working with collection specimens, and innovative molecular methods developed to tackle them. We also highlight possible applications of collection specimens, for taxonomy, ecology and evolution. The application of next-generation sequencing methods to museum and herbaria collections is still in its infancy. However, by giving researchers access to billions of specimens across time and space, it holds considerable promise for generating future discoveries across many fields.


Assuntos
Bancos de Espécimes Biológicos , Entomologia , Museus , Animais , Sequenciamento de Nucleotídeos em Larga Escala , História do Século XIX , Filogenia , Análise de Sequência de DNA
19.
Curr Opin Insect Sci ; 13: 16-23, 2016 02.
Artigo em Inglês | MEDLINE | ID: mdl-27436549

RESUMO

Our understanding on the phylogenetic relationships of insects has been revolutionised in the last decade by the proliferation of next generation sequencing technologies (NGS). NGS has allowed insect systematists to assemble very large molecular datasets that include both model and non-model organisms. Such datasets often include a large proportion of the total number of protein coding sequences available for phylogenetic comparison. We review some early entomological phylogenomic studies that employ a range of different data sampling protocols and analyses strategies, illustrating a fundamental renaissance in our understanding of insect evolution all driven by the genomic revolution. The analysis of phylogenomic datasets is challenging because of their size and complexity, and it is obvious that the increasing size alone does not ensure that phylogenetic signal overcomes systematic biases in the data. Biases can be due to various factors such as the method of data generation and assembly, or intrinsic biological feature of the data per se, such as similarities due to saturation or compositional heterogeneity. Such biases often cause violations in the underlying assumptions of phylogenetic models. We review some of the bioinformatics tools available and being developed to detect and minimise systematic biases in phylogenomic datasets. Phylogenomic-scale data coupled with sophisticated analyses will revolutionise our understanding of insect functional genomics. This will illuminate the relationship between the vast range of insect phenotypic diversity and underlying genetic diversity. In combination with rapidly developing methods to estimate divergence times, these analyses will also provide a compelling view of the rates and patterns of lineagenesis (birth of lineages) over the half billion years of insect evolution.


Assuntos
Genoma de Inseto/genética , Genômica/tendências , Insetos/classificação , Insetos/genética , Filogenia , Animais , Sequenciamento de Nucleotídeos em Larga Escala
20.
Front Zool ; 10(1): 55, 2013 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-24044698

RESUMO

BACKGROUND: Many scientific disciplines rely on correct taxon delineations and identifications. So does a great part of the general public as well as decision makers. Researchers, students and enthusiastic amateurs often feel frustrated because information about species remains scattered, difficult to access, or difficult to decipher. Together, this affects almost anyone who wishes to identify species or verify identifications. Many remedies have been proposed, but we argue that the role of natural history collections remains insufficiently appreciated. We suggest using state-of-the-art mass imaging technology and to join forces to create a global natural history metacollection on the internet, providing access to the morphology of tens of millions of specimens and making them available for automated digital image analysis. DISCUSSION: Robotic high-resolution imaging technology and fast (high performance) computer-based image stitching make it now feasible to digitize entire collection drawers typically used for arthropod collections, or trays or containers used for other objects. Resolutions of 500 megapixels and much higher are already utilized to capture the contents of 40x50 cm collection drawers, providing amazing detail of specimens. Flanked by metadata entry, this helps to create access to tens of thousands of specimens in days. By setting priorities and combining the holdings of the most comprehensive collections for certain taxa, drawer digitizing offers the unique opportunity to create a global, virtual metacollection.The taxonomic and geographic coverage of such a collection could never be achieved by a single institution or individual. We argue that by joining forces, many new impulses will emerge for systematic biology, related fields and understanding of biodiversity in general.Digitizing drawers containing unidentified, little-curated specimens is a contribution towards the beginning of a new era of online curation. It also will help taxonomists and curators to discover and process the millions of "gems" of undescribed species hidden in museum accessions. SUMMARY: Our proposal suggests creating virtual, high-resolution image resources that will, for the first time in history, provide access for expert scientists as well as students and the general public to the enormous wealth of the world's natural history collections. We foresee that this will contribute to a better understanding, appreciation and increased use of biodiversity resources and the natural history collections serving this cause.

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