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1.
New Phytol ; 232(3): 1414-1423, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34379798

RESUMO

Insect fluid-feeding on fossil vascular plants is an inconspicuous and underappreciated mode of herbivory that can provide novel data on the evolution of deep-time ecological associations and indicate the host-plant preferences of ancient insect herbivores. Previous fossil studies have documented piercing-and-sucking herbivory but often are unable to identify culprit insect taxa. One line of evidence are punctures and scale-insect impression marks made by piercing-and-sucking insects that occasionally provide clues to the systematic identities and relationships of particular insect herbivores. We report here the earliest occurrences of piercing and sucking on early angiosperms as evidenced by scale insect covers, impression marks, punctures and body fossils - notably a mealybug - from the Lower Cretaceous Rose Creek Flora of the Dakota Formation (c. 103 Ma), in southeastern Nebraska, USA. The mealybug, two other scale insect taxa, and several distinctive damage types on laurel leaves and seed-plant stems at Rose Creek document a diverse guild of piercing-and-sucking insects on early angiosperms. The discovery of an Early Cretaceous female mealybug indicates an early herbivorous association with a laurel host. These data provide direct evidence for co-associations and possible coevolution of scale insects and their plant hosts during early angiosperm diversification.


Assuntos
Hemípteros , Magnoliopsida , Animais , Evolução Biológica , Fósseis , Herbivoria , Insetos
2.
Mol Ecol ; 26(20): 5855-5868, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28833928

RESUMO

Hemipteran insects of the suborder Sternorrhyncha are plant sap feeders, where each family is obligately associated with a specific bacterial endosymbiont that produces essential nutrients lacking in the sap. Coccidae (soft scale insects) is the only major sternorrhynchan family in which obligate symbiont(s) have not been identified. We studied the microbiota in seven species from this family from Israel, Spain and Cyprus, by high-throughput sequencing of ribosomal genes, and found that no specific bacterium was prevalent and abundant in all the tested species. In contrast, an Ophiocordyceps-allied fungus sp.-a lineage widely known as entomopathogenic-was highly prevalent. All individuals of all the tested species carried this fungus. Phylogenetic analyses showed that the Ophiocordyceps-allied fungus from the coccids is closely related to fungi described from other hemipterans, and they appear to be monophyletic, although the phylogenies of the Ophiocordyceps-allied fungi and their hosts do not appear to be congruent. Microscopic observations show that the fungal cells are lemon-shaped, are distributed throughout the host's body and are present in the eggs, suggesting vertical transmission. Taken together, the results suggest that the Ophiocordyceps-allied fungus may be a primary symbiont of Coccidae-a major evolutionary shift from bacteria to fungi in the Sternorrhyncha, and an important example of fungal evolutionary lifestyle switch.


Assuntos
Hemípteros/microbiologia , Hypocreales/classificação , Microbiota , Animais , Chipre , DNA Fúngico/genética , Sequenciamento de Nucleotídeos em Larga Escala , Hypocreales/isolamento & purificação , Israel , Filogenia , Ribossomos/genética , Análise de Sequência de DNA , Espanha , Simbiose
3.
Artigo em Inglês | MEDLINE | ID: mdl-26861659

RESUMO

Scale insects (Hemiptera: Coccoidea) are small herbivorous insects found on all continents except Antarctica. They are extremely invasive, and many species are serious agricultural pests. They are also emerging models for studies of the evolution of genetic systems, endosymbiosis and plant-insect interactions. ScaleNet was launched in 1995 to provide insect identifiers, pest managers, insect systematists, evolutionary biologists and ecologists efficient access to information about scale insect biological diversity. It provides comprehensive information on scale insects taken directly from the primary literature. Currently, it draws from 23,477 articles and describes the systematics and biology of 8194 valid species. For 20 years, ScaleNet ran on the same software platform. That platform is no longer viable. Here, we present a new, open-source implementation of ScaleNet. We have normalized the data model, begun the process of correcting invalid data, upgraded the user interface, and added online administrative tools. These improvements make ScaleNet easier to use and maintain and make the ScaleNet data more accurate and extendable. Database URL: http://scalenet.info.


Assuntos
Biologia Computacional/métodos , Bases de Dados Bibliográficas , Bases de Dados Genéticas , Hemípteros/fisiologia , Animais , Biodiversidade , Evolução Biológica , Biologia , Ecologia , Geografia , Software
4.
Zootaxa ; 4006(1): 161-70, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26623763

RESUMO

The genus Dactylopius is the only genus at present in the family Dactylopiidae. Since the name Dactylopius was proposed in 1829, however, numerous other species names belonging to different families of scale insects have been combined with it and these are also listed. The present status and the family placement are also given for each species.


Assuntos
Hemípteros/classificação , Animais , Especificidade da Espécie
5.
Zootaxa ; 3980(3): 447-9, 2015 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-26249965

RESUMO

The adult female of Odonaspis bouldersensis Ben-Dov, new species, collected in the Boulders National Park, Queensland, Australia, off a species of Poaceae, is described.


Assuntos
Distribuição Animal , Hemípteros/anatomia & histologia , Hemípteros/classificação , Animais , Austrália , Feminino , Hemípteros/fisiologia , Especificidade da Espécie
6.
Zootaxa ; 3781: 1-99, 2014 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-24871950

RESUMO

A taxonomic revision is presented of the six Kermesidae species from Israel, namely, Kermes echinatus Balachowsky, K. greeni Bodenheimer, K. nahalali Bodenheimer, K. spatulatus Balachowsky, Nidularia balachowskii Bodenheimer, and K. hermonensis Spodek & Ben-Dov sp. n. Kermes bytinskii Sternlicht, syn. n. is established as a junior synonym of K. nahalali Bodenheimer and a lectotype for K. nahalali is designated. This study includes descriptions, redescriptions and illustrations of the adult female, adult male and all developmental stages for these six species. Keys are provided to distinguish between instars, adult females, adult males and immature stages for all species.


Assuntos
Hemípteros/anatomia & histologia , Hemípteros/classificação , Animais , Feminino , Hemípteros/crescimento & desenvolvimento , Israel , Masculino , Ninfa/anatomia & histologia , Ninfa/classificação
7.
Zookeys ; (246): 11-26, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23275748

RESUMO

Thefirst-instar nymph and the adult female of Kermes echinatus Balachowsky (Hemiptera, Coccoidea, Kermesidae) are described and illustrated. This species is compared with Kermes vermilio Planchon, a morphologically similar species known in the Palaeractic region.

8.
Zookeys ; (254): 23-45, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23378814

RESUMO

Descriptions and illustrations of the adult female and first-instar nymph of the kermesid Nidularia balachowskii Bodenheimer, based on the adult female lectotype and paralectotype (here designated), and new material collected from Israel are presented. A key for the identification of first-instar nymphs of Nidularia spp. is offered. Molecular identification of Nidularia balachowskii, using nucleotide sequences from the D2-D3 region of the 28S ribosomal gene, and the mitochondrial Cytochrome Oxidase I (COI) gene, is presented. Morphological and molecular analyses confirm that Nidularia balachowskii is closely related to other species within the Kermesidae. In Israel, this species develops only on Quercus ithaburensis and is univoltine. This is the first detailed report of Nidulariabalachowskii from Israel.

9.
Health Phys ; 95(6): 754-60, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19001902

RESUMO

A 40-keV, 5-mA DC deuteron beam was operated at the SARAF with the purpose of characterizing the ion source and the low-energy beam transport system. We used this opportunity to address radiological concern of operating an intense deuteron beam. Fast and thermal neutrons produced via the D(d,n) reaction were measured in the vicinity of the components intercepting the beam using various methods. We found that the neutron yield from implantation of a deuteron beam in a graphite matrix is of the order of 2 x 10(6) n s(-1) mA(-1) into 4pi.


Assuntos
Deutério/química , Saúde Radiológica , Hélio/química , Humanos , Índio/química , Isótopos , Nêutrons , Doses de Radiação
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