Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 63
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
PLoS One ; 15(9): e0238888, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32915879

RESUMO

The vast majority of species of velvet ants (Hymenoptera: Aculeata: Mutillidae) are ectoparasitoids of immature stages of other aculeate Hymenoptera (bees, wasps and ants). Due to their cryptic, furtive behaviour at the host nesting sites, however, even basic information on their biology, like host use diversity, is still unknown for entire subfamilies, and the known information, scattered in over two centuries of published studies, is potentially hiding tendencies to host specialization across velvet ant lineages. In this review, based on 305 host associations spanning 132 species in 49 genera and 10 main lineages (tribes/subfamilies), we explored patterns of host use in velvet ants. Overall, 15 families and 29 subfamilies of Aculeata are listed as hosts of mutillids, with a strong predominance of Apoidea (bees and apoid wasps: 19 subfamilies and 82.3% of host records). A series of bipartite networks, multivariate analyses and calculations of different indices suggested possible patterns of specialization. Host taxonomic spectrum (number of subfamilies) of velvet ants was very variable and explained by variation in the number of host records. Instead, we found a great variation of network-based host specialization degree and host taxonomic distinctness that did not depend on the number of host records. Differences in host use patterns seemed apparent across mutillid tribes/subfamilies, among genera within several tribes/subfamilies, and to lesser extent within genera. Taxonomic host use variation seemed not dependent on phylogeny. Instead, it was likely driven by the exploitation of hosts with different ecological traits (nest type, larval diet and sociality). Thus, taxonomically more generalist lineages may use hosts that essentially share the same ecological profile. Interestingly, closely related mutillid lineages often show contrasting combinations of host ecological traits, particularly sociality and larval diet, with a more common preference for ground-nesting hosts across most lineages. This review may serve as a basis to test hypotheses for host use evolution in this fascinating family of parasitoids.


Assuntos
Formigas/fisiologia , Abelhas/fisiologia , Evolução Molecular , Interações Hospedeiro-Parasita , Filogenia , Vespas/fisiologia , Animais , Formigas/classificação , Abelhas/classificação , Vespas/classificação
2.
Bull Entomol Res ; : 1-14, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32847632

RESUMO

The alien cynipid wasp Dryocosmus kuriphilus Yasumatsu, 1951 is a serious pest of chestnuts (Castanea spp.) in Japan, North America and Europe, causing fruit losses while inducing galls in buds. While D. kuriphilus galls have a recognizable and roughly invariable globular shape, their size varies, reaching up to 4 cm in diameter. Among other factors, such variation may depend on different climatic conditions in different attacked areas. Here, we sampled and measured 375 D. kuriphilus galls from 25 localities throughout the Iberian Peninsula, including both cold and rainy northern (Eurosiberian) areas and warm and dry central-southern (Mediterranean) areas, to test the effects of climate and geographical location on gall morphology. The analyses indicate that gall mass and volume follow a pattern that can be associated with a climatic cline. In particular, the Eurosiberian galls were smaller than the Mediterranean galls according to differences in climatic conditions. In the southern areas, the greater insolation regime does not allow the chestnut trees to be distributed at lower altitudes, but the high rainfall and humidity regime of the mountain enclaves allow their presence. These conditions of insolation and precipitation seem to influence the morphological characteristics of the galls of D. kuriphilus.

3.
Arthropod Struct Dev ; 57: 100950, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32413703

RESUMO

Several studies recently reported that specialized (oligolectic) bees, which collect pollen from few host plants, use, besides visual cues, specific volatiles to find their hosts. Generalist (polylectic) bees, on the other hand, likely have to recognize a wider range of volatiles because they forage on many plant species. Bee antennal sensory equipment may thus be under selection to optimize plant host recognition. This selection may have led to variation in sensory equipment morphology with diet specialization (lecty). We tested if lecty correlates with antennal morphology and abundance of the main olfactory/gustatory sensilla (sensilla trichoidea (ST), placoidea (SP), sensilla basiconica (SB)) in the genus Andrena (Hymenoptera: Andrenidae). Across 24 species, and after having controlled for body size, we found polylectic species to have a longer and narrower flagellomer F9 (the one with highest abundance of sensilla), and to have a greater ST density on F9, compared with oligolectic species. Neither SP density nor SB number varied with lecty. A cluster analysis furthermore depicted groups of species that reasonably reflect diet specialization. Our results are in line with the previously observed lower number of glomeruli in the brain of oligolectic, compared with polylectic, bees. A formal correction for phylogeny is necessary to confirm our preliminary conclusion that pollen diet specialization has driven the morphology of the peripheral sensory system in this bee genus.


Assuntos
Antenas de Artrópodes/ultraestrutura , Abelhas/ultraestrutura , Animais , Evolução Biológica , Dieta , Feminino , Microscopia Eletrônica de Varredura , Pólen , Sensilas/ultraestrutura
5.
Nutrients ; 12(5)2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32375317

RESUMO

The accumulation of adipose tissue increases the risk of several diseases. The fruits-intake, containing phytochemicals, is inversely correlated with their development. This study evaluated the effects of anthocyanin-rich tart cherries in diet-induced obese (DIO) rats. DIO rats were exposed to a high-fat diet with the supplementation of tart cherry seeds powder (DS) and seed powder plus juice (DJS). After 17 weeks, the DIO rats showed an increase of body weight, glycaemia, insulin, and systolic blood pressure. In the DS and DJS groups, there was a decrease of systolic blood pressure, glycaemia, triglycerides, and thiobarbituric reactive substances in the serum. In the DJS rats, computed tomography revealed a decrease in the spleen-to-liver attenuation ratio. Indeed, sections of the DIO rats presented hepatic injury characterized by steatosis, which was lower in the supplemented groups. In the liver of the DIO compared with rats fed with a standard diet (CHOW), a down-regulation of the GRP94 protein expression and a reduction of LC3- II/LC3-I ratio were found, indicating endoplasmic reticulum stress and impaired autophagy flux. Interestingly, tart cherry supplementation enhanced both unfolded protein response (UPR) and autophagy. This study suggests that tart cherry supplementation, although it did not reduce body weight in the DIO rats, prevented its related risk factors and liver steatosis.

6.
Nutrients ; 12(3)2020 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-32120798

RESUMO

Evidence suggests that obesity adversely affects brain function. High body mass index, hypertension, dyslipidemia, insulin resistance, and diabetes are risk factors for increasing cognitive decline. Tart cherries (Prunus Cerasus L.) are rich in anthocyanins and components that modify lipid metabolism. This study evaluated the effects of tart cherries on the brain in diet-induced obese (DIO) rats. DIO rats were fed with a high-fat diet alone or in association with a tart cherry seeds powder (DS) and juice (DJS). DIO rats were compared to rats fed with a standard diet (CHOW). Food intake, body weight, fasting glycemia, insulin, cholesterol, and triglycerides were measured. Immunochemical and immunohistochemical techniques were performed. Results showed that body weight did not differ among the groups. Blood pressure and glycemia were decreased in both DS and DJS groups when compared to DIO rats. Immunochemical and immunohistochemical techniques demonstrated that in supplemented DIO rats, the glial fibrillary acid protein expression and microglial activation were reduced in both the hippocampus and in the frontal cortex, while the neurofilament was increased. Tart cherry intake modified aquaporin 4 and endothelial inflammatory markers. These findings indicate the potential role of this nutritional supplement in preventing obesity-related risk factors, especially neuroinflammation.

7.
Eur J Hosp Pharm ; 27(2): 100-102, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32133136

RESUMO

Objective: Pulmonary arterial hypertension is a rare and progressive respiratory disease characterised by high blood pressure and vascular resistance producing right ventricular fatigue. In Italy, pulmonary hypertension can be treated with different drugs available on the market at different costs, and in the Marche region distributed exclusively by hospital pharmacies. The present study examined in an area of the Marche region the use of drugs specifically indicated for pulmonary hypertension, and evaluated how the introduction of the generic bosentan might lower pharmaceutical costs for the healthcare budget. Methods: The study examined oral administration prescriptions and costs using data from the Apotheke Gold (Record Data) database from 1 January 2012 to 31 August 2017. Results: Annually (from 1 January 2012 to 31 August 2017), an average of 4.83 patients were treated (prevalence of 102.35 cases per 1 million residents) with ambrisentan (Volibris), bosentan (Tracleer), macitentan (Opsumit), tadalafil (Adcirca) or sildenafil (Revatio). The total expenditure during the 5-year 8-month period was €472 405. Ambrisentan was by far the most expensive product overall, with a total expenditure of €222 380 for the period studied (a daily cost of €67.39), even though Tracleer had the highest cost for a day of treatment (a daily cost of €94.48, but a total expenditure of €163 976 for the period, due to its more recent marketing). Providing patients with the generic form bosentan in place of Tracleer would lower the costs dramatically. A very significant annual savings per patient of approximately €31 879 would be achieved, a striking 92.4% reduction in costs. Conclusion: The prevalence of pulmonary arterial hypertension reported for Camerino and its surrounding area in the Marches region is quite high compared with that reported by other authors for France and Scotland. The introduction of the generic bosentan would cut costs drastically. It is to be hoped that centralised procurement at the regional level would bring further savings.

8.
Insects ; 11(2)2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32093328

RESUMO

Insect brood parasites have evolved a variety of strategies to avoid being detected by their hosts. Few previous studies on cuckoo wasps (Hymenoptera: Chrysididae), which are natural enemies of solitary wasps and bees, have shown that chemical mimicry, i.e., the biosynthesis of cuticular hydrocarbons (CHC) that match the host profile, evolved in several species. However, mimicry was not detected in all investigated host-parasite pairs. The effect of host range as a second factor that may play a role in evolution of mimicry has been neglected, since all previous studies were carried out on host specialists and at nesting sites where only one host species occurred. Here we studied the cuckoo wasp Parnopes grandior, which attacks many digger wasp species of the genus Bembix (Hymenoptera: Crabronidae). Given its weak host specialization, P. grandior may either locally adapt by increasing mimicry precision to only one of the sympatric hosts or it may evolve chemical insignificance by reducing the CHC profile complexity and/or CHCs amounts. At a study site harbouring three host species, we found evidence for a weak but appreciable chemical deception strategy in P. grandior. Indeed, the CHC profile of P. grandior was more similar to all sympatric Bembix species than to a non-host wasp species belonging to the same tribe as Bembix. Furthermore, P. grandior CHC profile was equally distant to all the hosts' CHC profiles, thus not pointing towards local adaptation of the CHC profile to one of the hosts' profile. We conducted behavioural assays suggesting that such weak mimicry is sufficient to reduce host aggression, even in absence of an insignificance strategy, which was not detected. Hence, we finally concluded that host range may indeed play a role in shaping the level of chemical mimicry in cuckoo wasps.

9.
Handb Exp Pharmacol ; 254: 279-295, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31073870

RESUMO

While lifestyle modifications should be the first-line actions in preventing and treating obesity and eating disorders, pharmacotherapy also provides a necessary tool for the management of these diseases.However, given the limitations of current anti-obesity drugs, innovative treatments that improve efficacy and safety are needed.Since the discovery that the activation of the Nociceptin/Orphanin (N/OFQ) FQ peptide (NOP) receptor by N/OFQ induces an increase of food intake in laboratory animals, and the finding that this effect can be blocked by NOP antagonists, many NOP agonists and antagonists have been synthesized and tested in vitro and in vivo for their potential regulation of feeding behavior. Promising results seem to suggest that the N/OFQergic system may be a potential therapeutic target for the neural control of feeding behavior and related pathologies, especially in binge-like eating behavior.


Assuntos
Obesidade/metabolismo , Peptídeos Opioides , Receptores Opioides , Animais , Comportamento Alimentar , Peptídeos Opioides/química , Peptídeos Opioides/metabolismo
10.
Biochem Biophys Res Commun ; 505(3): 801-806, 2018 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-30297106

RESUMO

The aim of the study was to identify and functionally characterize novel candidate gene/s involved in the development of resistance to diet-induced obesity in rats. In a high-fat-diet (HFD) study of rats, we found subgroups which either developed resistance to HFD-induced obesity (DR) or showed an obesity-prone phenotype (DIO). Gene expression analysis in 10 samples (5 DIO vs 5 DR) was performed. The most promising gene, OR6C3 (orthologous with rat Olr984 and mouse Olfr788) was measured by qRT-PCR in paired samples of human visceral (Vis) and subcutaneous (SC) adipose tissue (AT) (n = 225) and in sub-fractions of adipocytes and cells of stromal vascular fraction. Gene expression analyses showed Olr984 with significantly reduced mRNA expression in DR rats. In the Vis AT of human samples we found an up-regulation of OR6C3 compared to SC AT, independent of gender, glucose tolerance or type 2 diabetes. We observed significantly lower levels of SC AT OR6C3 mRNA in subjects with obesity compared to those with normal-weight or overweight. OR6C3 is more expressed in SVF than in adipocytes. Olr984 could be a novel candidate gene related to diet-induced obesity in rats. Variation in human AT mRNA expression is related to obesity parameters and glucose homeostasis and linked to the regulatory role of insulin on the Olr984.


Assuntos
Tecido Adiposo/metabolismo , Perfilação da Expressão Gênica , Obesidade/tratamento farmacológico , Receptores Odorantes/genética , Animais , Dieta Hiperlipídica/efeitos adversos , Humanos , Resistência à Insulina , Camundongos , Obesidade/etiologia , Obesidade/genética , Ratos , Ratos Sprague-Dawley , Gordura Subcutânea
11.
BMC Ecol ; 18(1): 36, 2018 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-30236094

RESUMO

BACKGROUND: Predicting the patterns of range expansion of alien species is central to develop effective strategies for managing potential biological invasions. Here, we present a study on the potential distribution of the American cavity-nesting, Orthoptera-hunting and solitary wasp, Isodontia mexicana (Hymenoptera: Sphecidae), which was first detected as alien species in France in 1960 and now is present in many European countries. After having updated its current distribution, we estimated the environmental space (based on bioclimatic data and altitude) occupied by the species and subsequently predicted its environmental potential distribution under both present and future climatic conditions at global scale. RESULTS: The wasp lives in low-altitude areas of the Northern hemisphere with moderate temperatures and precipitation. The environmental space occupied in the invaded area is practically just a subset (42%) of that occupied in the native area, showing a process of environmental niche unfilling (i.e. the species only partially fills its environmental niche in the invaded range). Besides, I. mexicana could also live in other temperate areas, mainly in the Southern hemisphere, particularly close to the coasts. However, geographic (oceans) and/or climatic (tropical areas, mountain chains) barriers would prevent the species to reach these potential areas unless through human trade activity. The species could thus only reach, by active dispersion, the remaining invadable areas of Europe. Estimations for the future (2050 and 2070) predict an expansion through active dispersion towards North in the native range and towards North and East in the invaded range, but future conditions would not break down the current climatic barriers in the Southern hemisphere. CONCLUSIONS: Isodontia mexicana has not shifted its environmental niche in the invaded area. It could still occupy some new areas by active dispersion, but confined to Europe. The conspicuous niche unfilling shown by this wasp species could reflect the likely single introduction in Europe just a few decades ago. Furthermore, results stay in line with other studies that found niche unfilling rather than niche expansion in insects.


Assuntos
Distribuição Animal , Mudança Climática , Ecossistema , Espécies Introduzidas , Vespas/fisiologia , Animais , Europa (Continente) , França
12.
Microsc Microanal ; 24(2): 183-192, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29560839

RESUMO

Polistes paper wasps can be used to monitor trace metal contaminants, but the effects of pollution on the health of these insects are still unknown. We evaluated, in a south-eastern area of Spain, whether workers of Polistes dominula collected at urban and rural sites differ in health of midgut tissue and in fluctuating asymmetry, an estimate of developmental noise. We found that wasps collected at the urban sites had abundant lead (Pb)-containing spherites, which were less visible in wasps from the rural sites. Evident ultrastructural alterations in the epithelium of the midgut of the wasps collected at the urban sites included broken and disorganized microvilli, a high amount and density of heterochromatin in the nucleus of epithelial cells, cytoplasmic vacuolization and mitochondrial disruptions. Altogether, these findings suggest a negative effect on the transmembrane transport and a less efficient transcription. On the contrary, a healthy epithelium was observed in wasps from the rural sites. These differences may be preliminarily linked with levels of lead pollution, given that wasps from urban sites had double the Pb concentrations of wasps from rural sites. Level of fluctuating asymmetry was unrelated to wasp origin, thus suggesting no link between developmental noise and Pb-driven pollution.


Assuntos
Mucosa Intestinal/ultraestrutura , Vespas/anatomia & histologia , Vespas/ultraestrutura , Asas de Animais/anatomia & histologia , Animais , Cidades , Poluentes Ambientais/análise , Chumbo/análise , Espanha , Vespas/química
13.
Eur J Hosp Pharm ; 25(e2): e120-e125, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31157081

RESUMO

Background: Swallowing difficulties are arising in an increasing number of patients, especially in elderly people. When deglutition ability is completely compromised, enteral administration of a drug via feeding tubes is used. Licensed pharmacists have to compound the original solid forms to enable this drug therapy. Objectives: To evaluate the possibility of compounding original commercial tablets to produce a liquid formulation suitable for administering via a feeding tube. Methods: Two liquid formulations containing potassium canrenoate 5 mg/mL were prepared: a standard solution obtained by solubilising raw material and an extemporaneous preparation obtained by dissolving film-coated 100 mg tablets. Spectrophotometric determinations (UV range) of the drug established chemical stability of the analyte up to 60 days. Samples were tested for microbial growth. Gravimetric quantifications of liquid formulations were used to check any weight loss during the different steps before enteral administration. Results: UV data confirmed the chemical stability of potassium canrenoate up to 60 days. Samples showed no microbial growth. A higher weight loss was recorded in extemporaneous preparations than in the standard solution (10.7% vs 7.6%) according to the gravimetric quantification. Conclusion: It is possible to compound the original tablets into a liquid formulation suitable for administration via a feeding tube.

15.
Evolution ; 71(11): 2562-2571, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28791674

RESUMO

The cuticle of insects is covered by a layer of hydrocarbons (CHC), whose original function is the protection from desiccation and pathogens. However, in most insects CHC profiles are species specific. While this variability among species was largely linked to communication and recognition functions, additional selective forces may shape insect CHC profiles. Here, we show that in Philanthinae digger wasps (Crabronidae) the CHC profile coevolved with a peculiar brood-care strategy. In particular, we found that the behavior to embalm prey stored in the nest with hydrocarbons is adaptive to protect larval food from fungi in those species hunting for Hymenoptera. The prey embalming secretion is identical in composition to the alkene-dominated CHC profile in these species, suggesting that their profile is adaptively conserved for this purpose. In contrast, prey embalming is not required in those species that switched to Coleoptera as prey. Released from this chemical brood-care strategy, Coleoptera-hunting species considerably diversified their CHC profiles. Differential needs to successfully protect prey types used as larval food have thus driven the diversification of CHCs profiles of female Philanthinae wasps. To the best of our knowledge, this is the first evidence of a direct link between selection pressure for food preservation and CHC diversity.


Assuntos
Exoesqueleto/metabolismo , Evolução Molecular , Hidrocarbonetos/metabolismo , Comportamento Predatório , Vespas/genética , Exoesqueleto/química , Animais , Feminino , Hidrocarbonetos/análise , Vespas/fisiologia
16.
PeerJ ; 5: e3300, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28560094

RESUMO

BACKGROUND: Bumblebees (Hymenoptera: Apidae: Bombus) are well known for their important inter- and intra-specific variation in hair (or pubescence) color patterns, but the chemical nature of the pigments associated with these patterns is not fully understood. For example, though melanization is believed to provide darker colors, it still unknown which types of melanin are responsible for each color, and no conclusive data are available for the lighter colors, including white. METHODS: By using dispersive Raman spectroscopy analysis on 12 species/subspecies of bumblebees from seven subgenera, we tested the hypothesis that eumelanin and pheomelanin, the two main melanin types occurring in animals, are largely responsible for bumblebee pubescence coloration. RESULTS: Eumelanin and pheomelanin occur in bumblebee pubescence. Black pigmentation is due to prevalent eumelanin, with visible signals of additional pheomelanin, while the yellow, orange, red and brown hairs clearly include pheomelanin. On the other hand, white hairs reward very weak Raman signals, suggesting that they are depigmented. Additional non-melanic pigments in yellow hair cannot be excluded but need other techniques to be detected. Raman spectra were more similar across similarly colored hairs, with no apparent effect of phylogeny and both melanin types appeared to be already used at the beginning of bumblebee radiation. DISCUSSION: We suggest that the two main melanin forms, at variable amounts and/or vibrational states, are sufficient in giving almost the whole color range of bumblebee pubescence, allowing these insects to use a single precursor instead of synthesizing a variety of chemically different pigments. This would agree with commonly seen color interchanges between body segments across Bombus species.

17.
J Insect Physiol ; 100: 119-127, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28477982

RESUMO

Females of most aculeate Hymenoptera mate only once and males are therefore under a strong competitive pressure which is expected to favour the evolution of rapid detection of virgin females. In several bee species, the cuticular hydrocarbon (CHC) profile exhibited by virgin females elicits male copulation attempts. However, it is still unknown how widespread this type of sexual communication is within Aculeata. Here, we investigated the use of CHCs as mating cues in the digger wasp Stizus continuus, which belongs to the family (Crabronidae) from within bees arose. In field experiments, unmanipulated, recently emerged virgin female dummies promptly elicit male copulation attempts, whereas 1-4days old mated females dummies were still attractive but to a much lesser extent. In contrast, old (10-15days) mated female dummies did not attract males at all. After hexane-washing, attractiveness almost disappeared but could be achieved by adding CHC extracts from virgin females even on hexane-washed old mated females. Thus, the chemical base of recognition of females as appropriate mating partner by males is coded in their CHC profile. Accordingly, differences in CHC profiles can be detected between sexes, with males having larger amounts of alkenes and exclusive long-chain alkanes, and within females specially according to their mating status. Shortly after mating, almost all of the major hydrocarbons found on the cuticle of females undergo significant changes in their abundance, with a clear shift from short-chain to long-chain linear and methyl-branched alkanes. The timely detection of virgin females by males in S. continuus could be advantageous within the narrow period of female emergence, when male-male competition is strongest.


Assuntos
Hidrocarbonetos/metabolismo , Preferência de Acasalamento Animal , Atrativos Sexuais/metabolismo , Vespas/fisiologia , Animais , Feminino , Masculino
18.
Curr Biol ; 27(7): 1013-1018, 2017 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-28343967

RESUMO

Hymenoptera (sawflies, wasps, ants, and bees) are one of four mega-diverse insect orders, comprising more than 153,000 described and possibly up to one million undescribed extant species [1, 2]. As parasitoids, predators, and pollinators, Hymenoptera play a fundamental role in virtually all terrestrial ecosystems and are of substantial economic importance [1, 3]. To understand the diversification and key evolutionary transitions of Hymenoptera, most notably from phytophagy to parasitoidism and predation (and vice versa) and from solitary to eusocial life, we inferred the phylogeny and divergence times of all major lineages of Hymenoptera by analyzing 3,256 protein-coding genes in 173 insect species. Our analyses suggest that extant Hymenoptera started to diversify around 281 million years ago (mya). The primarily ectophytophagous sawflies are found to be monophyletic. The species-rich lineages of parasitoid wasps constitute a monophyletic group as well. The little-known, species-poor Trigonaloidea are identified as the sister group of the stinging wasps (Aculeata). Finally, we located the evolutionary root of bees within the apoid wasp family "Crabronidae." Our results reveal that the extant sawfly diversity is largely the result of a previously unrecognized major radiation of phytophagous Hymenoptera that did not lead to wood-dwelling and parasitoidism. They also confirm that all primarily parasitoid wasps are descendants of a single endophytic parasitoid ancestor that lived around 247 mya. Our findings provide the basis for a natural classification of Hymenoptera and allow for future comparative analyses of Hymenoptera, including their genomes, morphology, venoms, and parasitoid and eusocial life styles.


Assuntos
Evolução Biológica , Himenópteros/classificação , Proteínas de Insetos/genética , Animais , Himenópteros/genética , Himenópteros/fisiologia , Filogenia
19.
Zootaxa ; 4221(1): zootaxa.4221.1.4, 2017 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-28187675

RESUMO

We describe a new species of Corynura Spinola, a socially polymorphic genus within the bee tribe Augochlorini (Halictidae). We present a detailed description of both sexes of Corynura (Corynura) moscosensis n. sp. González-Vaquero, images of diagnostic morphological structures and antennal sensilla, floral associations, distributional data and notes on its nesting biology. Corynura moscosensis n. sp. is similar in appearance to C. (C.) chloromelas (Alfken), but it can be distinguished by the sculpturing of the mesoscutum and the hair types on the propodeum in the female, and by the genitalia and extent of the area exclusively covered by sensilla placoidea on the antennal flagellum of the male. A lectotype is designated for C. chloromelas. A Chilean Patagonian population of C. moscosensis n. sp. was observed to dig spatially clumped nests in an earth bank with a moderately hard and humid soil. The presence of multiple females within single nest tunnels is unusual and may preliminary suggest nest-sharing, but more data are necessary to define the social organization of this species. The species appears to be polylectic. Bee nests were attacked by satellite flies and possibly velvet ants.


Assuntos
Himenópteros , Animais , Argentina , Abelhas , Chile , Ecologia , Feminino , Masculino , Sensilas
20.
Arthropod Struct Dev ; 46(1): 39-48, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27450882

RESUMO

The inclusion of Zn in insect mandibles affects their hardness and is functional to their use during feeding or reproducing. However, little is known on the chemical/structural base of Zn enrichment. Here, we found that cathodoluminescence (CL) technique revealed two different types of CL spectra in the mandibles of Hymenoptera, depending on the Zn enrichment level assessed by Energy Dispersive X-ray Spectroscopy (EDS). Individuals having negligible traces to low % of Zn in their mandible teeth (≤3 wt%) presented a wide band of luminescence in the visible range which resembled those observed in the CC structures of graphite. This spectrum is probably characteristic for un-enriched cuticle, since it did not differ from those obtained from the Zn-lacking inner part of mandibles. Individuals with moderate to high % of Zn in their mandible teeth (≥7 wt%), instead, presented additional CL peaks in the ultraviolet range. Comparisons with different minerals of Zn suggest that these peaks could be related with OZnO bonds, with hydroxyl groups and with zinc-chlorine links (in agreement with Cl high levels detected by the EDS). Being a non-destructive technique, CL allows large comparative studies of the chemistry of metal-enriched insect cuticle even using unique specimens, such as those deposited in Natural History Museums.


Assuntos
Himenópteros/fisiologia , Boca/fisiologia , Zinco/química , Animais , Abelhas/fisiologia , Cloro/química , Feminino , Proteínas de Insetos/metabolismo , Luminescência , Microscopia Eletrônica de Varredura , Espectrometria por Raios X , Espectrofotometria Ultravioleta , Vespas/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA