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1.
Insect Sci ; 27(1): 58-68, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29676854

RESUMO

"Candidatus Liberibacter solanacearum" (Lso) are phloem-restricted and unculturable Gram-negative bacteria. Presently five haplotypes have been identified worldwide; but only haplotypes A and B are associated with the vector Bactericera cockerelli (Sulc.) in the Americas. Previous studies showed that Lso-infection reduces B. cockerelli reproductive output and that Lso haplotype B is more pathogenic than Lso haplotype A. To understand the interaction of Lso haplotype B and B. cockerelli, the fitness of Lso-free and Lso B-infected insects, and the expression of vitellogenin (BcVg1-like), a gene involved directly in the insect reproduction were analyzed. Statistical differences in the number of eggs oviposited, and the total number of progeny nymphs and adults were found among crosses of insects with or without Lso. Significant differences in sex proportions were found between Lso B-infected and Lso-free crosses: a higher proportion of F1 adult females were obtained from Lso B-infected mothers. A significant reduction of BcVg1-like was observed in crosses performed with Lso B-infected females compared to the Lso-free insects. In female cohorts of different age, a significant reduction of BcVg1-like expression was measured in 7-d-old Lso B-infected females (virgin and mated) compared with 7-d-old Lso-free females (virgin and mated), respectively. The reduction of BcVg1-like transcript was associated with a lower number of developing oocytes observed in female's reproductive systems. Overall, this study represents the first step to understand the interaction of Lso B with B. cockerelli, highlighting the effect of Lso B infection on egg production, BcVg1-like expression, and oocyte development.


Assuntos
Aptidão Genética , Hemípteros/fisiologia , Rhizobiaceae/fisiologia , Vitelogênese , Animais , Hemípteros/genética , Hemípteros/crescimento & desenvolvimento , Hemípteros/microbiologia , Lycopersicon esculentum/microbiologia , Lycopersicon esculentum/fisiologia , Ninfa/genética , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Ninfa/fisiologia , Doenças das Plantas/microbiologia
2.
Insect Sci ; 27(1): 86-98, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29749703

RESUMO

Bacterial endosymbionts play important roles in ecological traits of aphids. In this study, we characterize the bacterial endosymbionts of A. gossypii collected in Karaj, Iran and their role in the performance of the aphid. Our results indicated that beside Buchnera aphidicola, A. gossypii, also harbors both Hamiltonella defensa and Arsenophonus sp. Quantitative PCR (qPCR) results revealed that the populations of the endosymbionts increased throughout nymphal development up to adult emergence; thereafter, populations of Buchnera and Arsenophonus were diminished while the density of H. defensa constantly increased. Buchnera reduction caused prolonged development and no progeny production. Furthermore, secondary symbiont reduction led to reduction of the total life span and intrinsic rate of natural increase as well as appearance of the deformed dead offspring in comparison with the control insects. Reduction of the secondary symbionts did not affect parasitism rate of the aphid by the parasitic wasp Aphidius matricariae. Together these findings showed that H. defensa and Arsenophonus contributed to the fitness of A. gossypii by enhancing its performance, but not through parasitoid resistance.


Assuntos
Afídeos/microbiologia , Afídeos/fisiologia , Buchnera/fisiologia , Enterobacteriaceae/fisiologia , Simbiose , Animais , Afídeos/crescimento & desenvolvimento , Irã (Geográfico) , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Reprodução , Especificidade da Espécie
3.
Insect Sci ; 27(1): 69-85, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29797656

RESUMO

Bacterial endosymbionts have enabled aphids to adapt to a range of stressors, but their effects in many aphid species remain to be established. The bird cherry-oat aphid, Rhopalosiphum padi (Linnaeus), is an important pest of cereals worldwide and has been reported to form symbiotic associations with Serratia symbiotica and Sitobion miscanthi L-type symbiont endobacteria, although the resulting aphid phenotype has not been described. This study presents the first report of R. padi infection with the facultative bacterial endosymbiont Hamiltonella defensa. Individuals of R. padi were sampled from populations in Eastern Scotland, UK, and shown to represent seven R. padi genotypes based on the size of polymorphic microsatellite markers; two of these genotypes harbored H. defensa. In parasitism assays, survival of H. defensa-infected nymphs following attack by the parasitoid wasp Aphidius colemani (Viereck) was 5 fold higher than for uninfected nymphs. Aphid genotype was a major determinant of aphid performance on two Hordeum species, a modern cultivar of barley H. vulgare and a wild relative H. spontaneum, although aphids infected with H. defensa showed 16% lower nymph mass gain on the partially resistant wild relative compared with uninfected individuals. These findings suggest that deploying resistance traits in barley will favor the fittest R. padi genotypes, but symbiont-infected individuals will be favored when parasitoids are abundant, although these aphids will not achieve optimal performance on a poor quality host plant.


Assuntos
Afídeos/microbiologia , Enterobacteriaceae/fisiologia , Simbiose , Animais , Afídeos/genética , Afídeos/crescimento & desenvolvimento , Genótipo , Ninfa/genética , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Escócia
4.
Insect Sci ; 27(1): 33-48, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29845727

RESUMO

Feeding behavior and plant response to feeding were studied for the aphid Aphis gossypii Glover on susceptible and resistant melons (cv. Iroquois and TGR-1551, respectively). Average phloem phase bout duration on TGR-1551 was <7% of the duration on Iroquois. Sixty-seven percent of aphids on TGR-1551 never produced a phloem phase that attained ingestion (EPG waveform E2) in contrast to only 7% of aphids on Iroquois. Average bout duration of waveform E2 (scored as zero if phloem phase did not attain E2) on TGR-1551 was <3% of the duration on Iroquois. Conversely, average bout duration of EPG waveform E1 (sieve element salivation) was 2.8 times greater on TGR-1551 than on Iroquois. In a second experiment, liquid nitrogen was used to rapidly cryofix leaves and aphids within a few minutes after the aphids penetrated a sieve element. Phloem near the penetration site was then examined by confocal laser scanning microscopy. Ninety-six percent of penetrated sieve elements were occluded by protein in TGR-1551 in contrast to only 28% in Iroquois. Usually in TGR-1551, occlusion was also observed in nearby nonpenetrated sieve elements. Next, a calcium channel blocker, trivalent lanthanum, was used to prevent phloem occlusion in TGR-1551, and A. gossypii feeding behavior and the plant's phloem response were compared between lanthanum-treated and control TGR-1551. Lanthanum treatment eliminated the sieve element protein occlusion response and the aphids readily ingested phloem sap from treated plants. This study provides strong evidence that phloem occlusion is a mechanism for resistance against A. gossypii in TGR-1551.


Assuntos
Antibiose , Afídeos/fisiologia , Cucumis melo/fisiologia , Animais , Afídeos/crescimento & desenvolvimento , Comportamento Alimentar , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia
5.
Insect Sci ; 27(1): 170-184, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29938899

RESUMO

Elevated concentrations of atmospheric CO2 can alter plant secondary metabolites, which play important roles in the interactions among plants, herbivorous insects and natural enemies. However, few studies have examined the cascading effects of host plant secondary metabolites on tri-trophic interactions under elevated CO2 (eCO2 ). In this study, we determined the effects of eCO2 on the growth and foliar phenolics of Medicago truncatula and the cascading effects on two color genotypes of Acyrthosiphon pisum (pink vs. green) and their parasitoid Aphidius avenae in the field open-top chambers. Our results showed that eCO2 increased photosynthetic rate, nodule number, yield and the total phenolic content of M. truncatula. eCO2 had contrasting effects on two genotypes of A. pisum; the green genotype demonstrated increased population abundance, fecundity, growth and feeding efficiency, while the pink genotype showed decreased fitness and these were closely associated with the foliar genstein content. Furthermore, eCO2 decreased the parasitic rate of A. avenae independent of aphid genotypes. eCO2 prolonged the emergence time and reduced the emergence rate and percentage of females when associated with the green genotype, but little difference, except for increased percentage of females, was observed in A. avenae under eCO2 when associated with the pink genotype, indicating that parasitoids can perceive and discriminate the qualities of aphid hosts. We concluded that eCO2 altered plant phenolics and thus the performance of aphids and parasitoids. Our results indicate that plant phenolics vary by different abiotic and biotic stimuli and could potentially deliver the cascading effects of eCO2 to the higher trophic levels. Our results also suggest that the green genotype is expected to perform better in future eCO2 because of decreased plant resistance after its infestation and decreased parasitic rate.


Assuntos
Afídeos/fisiologia , Afídeos/parasitologia , Dióxido de Carbono/metabolismo , Medicago truncatula/química , Fenóis/metabolismo , Vespas/fisiologia , Animais , Afídeos/crescimento & desenvolvimento , Herbivoria , Interações Hospedeiro-Parasita , Larva/crescimento & desenvolvimento , Larva/fisiologia , Ninfa/crescimento & desenvolvimento , Ninfa/parasitologia , Ninfa/fisiologia , Vespas/crescimento & desenvolvimento
6.
Zootaxa ; 4608(2): zootaxa.4608.2.9, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31717152

RESUMO

The lack of nymph-adult associations limits our knowledge of the ecology, history and sensitivity of aquatic insects. In this study, the new species, Anacroneuria suerre sp. nov is described from Costa Rica based on the male, female, and nymphal stages. We briefly discuss the use of Plecoptera in ecotoxicological studies.


Assuntos
Lepidópteros , Animais , Costa Rica , Ecologia , Feminino , Insetos , Masculino , Ninfa
7.
Zootaxa ; 4695(3): zootaxa.4695.3.3, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31719350

RESUMO

Two new species of Miroculis Edmunds, 1963 (Ephemeroptera: Leptophlebiidae) are described, diagnosed and illustrated based on adults and/or nymphs collected in Brazil and Colombia. Both species share an uncommon genitalia morphology, which includes a long penis that is curved at base and a long styliger plate. In the case of the species from Brazil, which is also described based on nymphs, gills are devoid of the characteristic lateral lobes found in the other species of the genus.


Assuntos
Ephemeroptera , Animais , Brasil , Colômbia , Brânquias , Masculino , Ninfa
8.
Zootaxa ; 4695(1): zootaxa.4695.1.4, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31719365

RESUMO

The study of immature stages in Pentatomidae contributes to the knowledge in several areas, mainly systematics, ecology and agriculture. In faunistic inventories, nymphs comprise a significant part of the specimens collected, which often cannot be identified due to lack of knowledge about the immature. Here, we describe the external morphology of eggs and nymphal stages of Runibia perspicua (Fabricius, 1798). The egg is barrel-shaped with the surface of chorium covered by spines, forming polygonal markings interconnected by sheets, similar as observed in some species of Carpocorini. In all the nymphal instars the abdomen is characterized by having rounded reddish spots and an orange/yellow longitudinal macula in the middle of each abdominal tergite, from abdominal segment II to VII. The first instar is the most distinctive, standing out mainly by the head and thorax totally brown. From the second instar the head and thorax acquire pale color with irregular brown spots. The labium presents significant variations in size along the ontogenetic development showing a non-isometric pattern, when compared to the total length of the body. Illustrations and photographs of all the immature stages and the detailed morphology of some structures in SEM are provided.


Assuntos
Hemípteros , Heterópteros , Animais , Cor , Ecologia , Ninfa , Óvulo
9.
Zootaxa ; 4577(1): zootaxa.4577.1.2, 2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-31715734

RESUMO

The aim of this research was to study the diversity of jumping plant-lice parasitoids and to investigate their potential in biological control applicable to cultivated and ornamental plants. Thirteen species from six genera of encyrtid wasps (Hymenoptera, Chalcidoidea, Encyrtidae) were reared from 24 species of jumping plant-lice (Hemiptera, Psylloidea) in Serbia. A total of 689 encyrtid wasps were collected since 2003 from 51 localities, reared from hosts. The richest genera are Psyllaephagus with four species (P. belanensis (Hoffer), P. fulvipes Erdös, P. procerus Mercet and Psyllaephagus sp.) and Syrphophagus with three species (S. aphidivorus (Mayr), S. taeniatus (Förster) and S. ariantes (Walker)). The most common species, comprising about half of the reared specimens, is Prionomitus mitratus (Dalman). Eight species are new to Serbia: Microterys annulatus (Erdös, 1957), Prionomitus tiliaris (Dalman), Psyllaephagus belanensis, P. fulvipes, P. procerus, Sectiliclava cleone (Walker), Syrphophagus ariantes and Trechnites flavipes (Mercet). Psyllaephagus fulvipes was reared from the nymphs of Craspedolepta conspersa (Löw), the only known host of this species so far. In the present study, 27 new host associations were found.


Assuntos
Afídeos , Besouros , Hemípteros , Himenópteros , Vespas , Animais , Ninfa , Sérvia
10.
Zootaxa ; 4568(3): zootaxa.4568.3.1, 2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-31715842

RESUMO

Three new species of zerconid mites of the genus Halozercon are described and illustrated: H. tigerek sp. n., H. kazachok sp. n. and H. capitaneus sp. n., on the basis of material collected from litter and soil in the Altai Mountains in South Siberia, Russia. Morphological characters of adults, nymphs and larva for new Halozercon species are given.


Assuntos
Ácaros , Animais , Ninfa , Federação Russa , Sibéria , Solo
11.
Zootaxa ; 4683(2): zootaxa.4683.2.7, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31715930

RESUMO

Thraulodes Ulmer, 1920 is one of the most abundant and widespread genera of Leptophlebiidae represented by 66 species (Barber-James et al. 2013; Gonçalves et al. 2013; Lima et al. 2013; Souto et al. 2014; Zúñiga et al. 2015; Boldrini et al. 2018; Campos Mariano 2019). Its distribution extends from Central Argentina in the Neotropics to the Neartic Region. For Brazil, 23 species are known (Salles Boldrini 2019), but only seven species are known from both adult and nymphal stages: T. bonito Gonçalves, Da-Silva Nessimian; T. cochunaensis Domínguez; T. daidaleus Traver Edmunds; T. jones Gonçalves, Da-Silva Nessimian; T. itatiajanus Traver Edmunds; T. schlingeri Traver Edmunds and T. traverae Thew (Thew 1960; Traver Edmunds 1967; Domínguez 1987; Lopes et al. 2003; Gonçalves et al. 2010; Gonçalves et al. 2013).


Assuntos
Bivalves , Ephemeroptera , Animais , Argentina , Brasil , Ninfa
12.
Zootaxa ; 4671(3): zootaxa.4671.3.7, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31716046

RESUMO

A new species of sand-burrowing mayfly (Ephemeroptera: Behningiidae), Behningia nujiangensis Zhou Bisset, is described based on more than 50 nymphs collected from the Nujiang River in Yunnan Province, P.R. China. This is the first species of the family Behningiidae discovered in China. It is also the second species of genus Behningia, and the third species of the family Behningiidae collected from the Oriental biogeographic region. The shapes of the labrum and the labium in B. nujiangensis are markedly different from those found in other species of Behningia. Differences in the mandibles, the galea-lacina of maxillae, and both the prothoracic and metathoracic legs differentiate B. nujiangensis from both B. baei and B. ulmeri. The biology of and conservation challenges for B. nujiangensis are also briefly discussed.


Assuntos
Ephemeroptera , Animais , China , Ninfa , Rios
13.
Zootaxa ; 4590(5): zootaxa.4590.5.4, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31716075

RESUMO

Two new species of treehoppers are described from Colombia: Calloconophora estellae sp. nov. and Problematode robertoi sp. nov. The first from the Western foothills of the Cordillera Occidental, and Eastern foothills of the North of the Cordillera Central toward the Magdalena Medio region. Problematode robertoi sp. nov. is described from highlands, nearby Los Nevados National Natural Park. Description of the nymphs, notes on their biology, and comments about the taxonomic position and distribution of each species are included. This is the first record of a Calloconophora species secreting a waxy substance on branches close to eggs and/or nymphs, and the first record of the genus Problematode in Colombia (previously only known from Venezuela). Additionally, based on characters of a late-instar nymph exuviae, the position of Problematode within the Membracidae subfamilies is discussed.


Assuntos
Hemípteros , Distribuição Animal , Animais , Colômbia , Ninfa , Óvulo , Venezuela
14.
Zootaxa ; 4586(3): zootaxa.4586.3.12, 2019 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-31716125

RESUMO

Six species of Bungona Harker, including three species of the subgenus Centroptella Braasch Soldán and three species of subgenus of Chopralla Waltz McCafferty, are reported from China. Of which, three new species, Bungona (Centroptella) ovata sp. nov., Bungona (Centroptella) quadrata sp. nov. and Bungona (Chopralla) bifida sp. nov., are described based on nymphal materials. In addition, Bungona (Chopralla) liebenauae (Soldán, Braasch Muu, 1987) that was previously known only from Vietnam is newly recorded in China. An identification key to Bungona species known from Oriental Region is presented.


Assuntos
Ephemeroptera , Animais , China , Ninfa , Vietnã
15.
Zootaxa ; 4585(2): zootaxa.4585.2.6, 2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-31716171

RESUMO

The putative female, nymph and egg of Enderleina preclara are described from specimens collected in the Kukenán-tepui foothills and Acopán-tepui foothills and plateau of Venezuela. Morphological and molecular approaches were employed to characterize these stages. Diagnostic keys for males and females of the described Enderleina species are also presented. The nymph is also morphologically compared with those of other Enderleina species. Comments on the ecology of this species and erroneous information regarding the putative type locality of E. preclara are provided.


Assuntos
Insetos , Animais , Ecologia , Feminino , Masculino , Ninfa , Venezuela
16.
Zootaxa ; 4585(2): zootaxa.4585.2.13, 2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-31716178

RESUMO

The nymphal stages of Tricorythodes pemonensis n. comb. and T. zagaia n.comb. are firstly described. The nymphal characters as well as the characteristic swelling at the base of second forceps segment in male imago justify moving them from Macunahyphes to Tricorythodes. Additionally, other three species described in Macunahyphes are also transferred to Tricorythodes: Tricorythodes araca (Souto Salles) new comb., Tricorythodes eduardoi (Almeida Mariano) new comb., and Tricorythodes incognitus (Molineri et al.) new comb. Macunahyphes australis is the only species that remains in the genus.


Assuntos
Ephemeroptera , Heterópteros , Animais , Colômbia , Masculino , Ninfa
17.
Zootaxa ; 4623(1): zootaxa.4623.1.8, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31716278

RESUMO

The detailed morphology and phylogenetic positon of Parafronurus youi Zhou Braasch, 2003 have not been discussed especially so far. In this study, we re-describe and illustrate all stages in more detail. Compared to other genera in the subfamily Ecdyonurinae, the nymph of P. youi is characterized by rounded supracoxal spurs, rounded rectangular head capsule, dense setae on dorsal side of labrum, simple proximal and distal dentisetae, primarily swimming setae of caudal filaments. Upon the latter two characters, this genus seems closer to Asian Rhithrogeniella Ulmer, 1939.


Assuntos
Ephemeroptera , Animais , Ninfa , Filogenia , Natação
18.
Zootaxa ; 4613(1): zootaxa.4613.1.10, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31716432

RESUMO

The male, female, and nymph of the leuctrid Rhopalopsole hamata Yang Yang, 1995, originally known from Zhejiang, an eastern coastal province of China, are redescribed and illustrated. This new material is from Jiangsu, an eastern-central coastal province of China. Brief biological data is also provided for this species. In addition, a species checklist of the Rhopalopsole dentata group from China is provided. The type localities of these group are mainly in the coastal areas of southeastern China.


Assuntos
Insetos , Animais , China , Feminino , Masculino , Neópteros , Ninfa
19.
Zootaxa ; 4565(4): zootaxa.4565.4.8, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-31716456

RESUMO

A new mayfly species, Choroterpes (Euthraulus) kalladaensis sp. n. is described based on nymphs and subimagoes from South India. The nymph of Choroterpes (Euthraulus) kalladaensis sp. n. is characterized by a labrum with antero-median emargination well broad and 'V' shaped, femora with two black spots on median and basal region, claw with 2 sections of 13 denticles with 3 smaller serrations, posteriolateral spines present on segment 2-9, paraprocts smooth with pores and their inner margin with small triangular spines and outer margin with long setae and in the subimago the fore wing has four intercalary veins between costa and subcosta, penis lobes are short, membranous, separated apically and covered with minute setae. Taxonomic notes are given to distinguish this new species from closely related species.


Assuntos
Ephemeroptera , Animais , Índia , Masculino , Ninfa , Coluna Vertebral
20.
Zootaxa ; 4564(2): zootaxa.4564.2.4, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-31716503

RESUMO

The nymphal morphology of the family Rhopalidae is well known for several species, most of which are pests. Ontogenetic changes in morphology are described in detail for two members from two tribes of the subfamily Rhopalinae, Rhopalini: Rhopalus (Aeschyntelus) maculatus (Fieber) and Chorosomini: Chorosoma schillingii (Schilling). Keys to the nymphal instars of both species are provided. The special types of nymphal setae and lateral abdominal processes are described in R. maculatus. The ontogenetic development of abdominal trichobothria is described, and the known trichobothrial patterns within the Rhopalidae are discussed.


Assuntos
Hemípteros , Heterópteros , Animais , Tamanho Corporal , Ninfa , Tamanho do Órgão , Sensilas
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