First screening of bacterial communities of Microdon myrmicae and its ant host: do microbes facilitate the invasion of ant colonies by social parasites?

Abstract Many studies have highlighted how numerous bacteria provide their hosts essential nutrients or protection against pathogens, parasites and predators. Nevertheless, the role of symbiotic microorganisms in the interactions between social insects and their parasites is still poorly known. Microdon (Diptera, Syrphidae) is a peculiar fly genus whose larvae are able to successfully infiltrate ant colonies and feed upon the ant brood. Using high throughput 16S rRNA gene amplicon sequencing, we provide the first microbiome survey of Mi. myrmicae larvae and larvae and workers of its host, Myrmica scabrinodis, collected from two sites in England. We analyzed the microbiome of the external surface of the cuticle and the internal microbiome of the body separately. The results clearly show that the Mi. myrmicae microbiome significantly differs from that of its host, while no substantial dissimilarity was detected across the microbiome of ant workers and ant larvae. Microdon myrmicae microbiome varies across the two analyzed sites suggesting that bacteria communities of Mi. myrmicae are derived from the environment rather than by horizontal transmission between hosts and parasites. Families Streptococcaceae, Carnobacteriaceae and Rizhobiaceae are dominant in My. scabrinodis, and Spiroplasma is dominant in ant workers. Microbiome of Mi. myrmicae larvae is mainly characterized by the family Anaplasmataceae, with Wolbachia as predominant genus. Interestingly, we found Serratia within both Mi. myrmicae and Myrmica larvae. Bacteria of this genus are known to produce a family of pyrazines commonly involved in ant communication, which could play a role in Microdon/ant interaction

Strange loves: a remarkable case of aberrant copulation in beetles (Coleoptera: Meloidae, Chrysomelidae)

A case of copulation between two mimic and repellent beetle species (a male of Timarcha fracassii, and a female of Meloe autumnalis), belonging to distinct families (Chrysomelidae, Meloidae), is recorded

Detailed morphological descriptions of the immature stages of the ant parasite Microdon mutabilis (Diptera: Syrphidae: Microdontinae) and a discussion of its functional morphology, behaviour and host specificity

The myrmecophilous immature stages of hover flies of the genus Microdon Meigen, 1803 (Diptera, Syrphidae) are still poorly known and only about 15 species were previously incompletely described and/or illustrated using light microscopy based on occasional findings mainly of pupae and third instar larvae. The exceptional finding of a large number of second and third instar larvae and pupae (159 specimens) of Microdon mutabilis (Linnaeus, 1758) inside the nest of a new host species, Formica cunicularia Latreille,1798, enabled us to rear them and obtain a great number of eggs and first instar larvae. We filmed and described the feeding behaviour and locomotion of these highly derived slug-like larvae. Combining light, fluorescence and scanning electron (SEM) microscopy, we describe in detail and illustrate the external features of all the immature stages of M. mutabilis (eggs, larvae and pupae). Covering the entire chorion of the egg is a peculiar microsculpture composed of volcano-like processes. The three larval instars strongly differ from each other, especially at the level of the shape of the body, the posterior spiracular tubercle and the cephaloskeleton. SEM microscopy was used to describe in detail the microsculpture, sensorial structures, spiracles and cephalic appendages of larvae and pupae. Fluorescence microscopy was used to reveal the exceptional presence of resilin in the external layer of the posterior spiracular tubercle in first instar larvae. The possible functional significance of these structures is discussed

Qualidade dos menus infantis em shoppings centers do Brasil

Objectives: characterize the availability and assess the nutritional quality of children’s menus ofered in regular and fast food restaurants in Brazilian malls. Methods: this is an observational and cross-sectional study. Data were collected on the websites of each restaurant and in food sales applications, with a questionnaire consisting of two sections: characterization of the restaurant and characterization of the children’s menu. Data collection took place in ten capitals in the fve regions of Brazil. Results: 116 children’s menus were evaluated. The study identifed a higher number of regular (n=70, 60%) than fast-food (n=46,40%) restaurants. The cooking methods most used in the main dishes were grilled (n=236, 64%) and boiled (n=74, 20%), and in the side dishes were boiled (n=204, 53%) and fried (n=109, 28%). Only 40% (n=46) of the menus contained vegetables. Less than 10% (n=seven) ofered fruit as dessert, 31% (n = 36) had drinks included in the children’s menu and 22% (n=25) ofered gifts associated with the menu. Only 32 (28%) restaurants had the combination of beans and rice. Conclusion: most of the options ofered to children were of low nutritional quality, with low ofer of vegetables, fruits and the traditional beans and rice. The beverages included in the menus, most of them sugary, can contribute to a high-energy intake. There is a need to provide healthy options and encourage these choices.Objetivos: caracterizar a disponibilidade e a qualidade nutricional dos menus infantis nos restaurantes e estabelecimentos de fast-foods em Shoppings Centers no Brasil. Métodos: trata-se de um estudo observacional e transversal. Os dados foram coletados nos websites de cada estabelecimento e em aplicativos de vendas de alimentos, com questionário composto por duas seções: Caracterização do estabelecimento e caracterização do menu infantil. A coleta dos dados ocorreu em dez capitais distribuídas nas cinco regiões do Brasil. Resultados: foram avaliados 116 menus infantis. Maior número de estabelecimentos foi classifcado como restaurante do que fast-food. Os métodos de cocção mais utilizados nos pratos principais foram grelhados (n=236, 64%) e cozidos (n=74, 20%), e nos acompanhamentos foram cozidos (n=204, 53%) e fritos (n=109, 28%). Apenas 40% (n=46) dos menus continham hortaliças. Menos de 10% (n=sete) ofertavam fruta como sobremesa; 31% (n=36) constavam bebida inclusa no menu infantil; 22% (n=25) ofereciam brindes associados ao menu. Apenas 32 (28%) estabelecimentos apresentavam a combinação feijão e arroz. Conclusão: a maioria das opções ofertadas às crianças era de baixa qualidade nutricional, com pouca oferta de hortaliças, frutas e do tradicional feijão e arroz. As bebidas incluídas nos menus, a maioria açucaradas, podem contribuir para uma elevada ingestão energética. Constata-se a necessidade de disponibilizar opções saudáveis e incentivar essas escolhas

Current approaches for treatment of coronary chronic occlusions

Introduction: Coronary chronic total occlusions (CTO) represent a challenging subset in interventional cardiology. Areas covered: During the last decade, improvements in materials, techniques, and meticulous pre-procedural lesion assessment have increased the success rate in CTO lesions. Several scores have been developed to address overall lesion evaluation and help select the most appropriate treatment strategy. In addition, specific algorithms such as the hybrid algorithm have been introduced to provide a framework for CTO operators and a rapid management of the various challenging aspects of the procedure. The hybrid approach requires opera

Foe to frenemy: predacious ant nest beetles use multiple strategies to fully integrate into ant nests

Ant nest beetles (Carabidae, Paussinae, Paussini; Paussus) are renowned myrmecophiles, mostly known for their bizarre and diverse antennal shape. While little is known about their development, behavior and host range, we do know they spend most of their lives inside ant nests, feeding upon the hemolymph of ant brood and teneral workers. Recent findings suggest these beetles use a surprisingly complex strategy for interacting and deceiving ants. They have managed to break into multiple communication channels that ants use to recognize and communicate with one another in order to deceive the ants and profit from the rich resources of the nest. Mounting evidence from structural, chemical, acoustic, and behavioral studies support the hypothesis that Paussus is among the most highly integrated parasite of social insects known to date

Social antagonism facilitates supergene expansion in ants

Antagonistic selection has long been considered a major driver of the formation and expansion of sex chromosomes. For example, sexually antagonistic variation on an autosome can select for suppressed recombination between that autosome and the sex chromosome, leading to a neo-sex chromosome. Autosomal supergenes, chromosomal regions containing tightly linked variants affecting the same complex trait, share similarities with sex chromosomes, raising the possibility that sex chromosome evolution models can explain the evolution of genome structure and recombination in other contexts. We tested this premise in a Formica ant species, wherein we identified four supergene haplotypes on chromosome 3 underlying colony social organization and sex ratio. We discovered a novel rearranged supergene variant (9r) on chromosome 9 underlying queen miniaturization. The 9r is in strong linkage disequilibrium with one chromosome 3 haplotype (P2) found in multi-queen (polygyne) colonies. We suggest that queen miniaturization is strongly disfavored in the single-queen (monogyne) background and is thus socially antagonistic. As such, divergent selection experienced by ants living in alternative social "environments" (monogyne and polygyne) may have contributed to the emergence of a genetic polymorphism on chromosome 9 and associated queen-size dimorphism. Consequently, an ancestral polygyne-associated haplotype may have expanded to include the polymorphism on chromosome 9, resulting in a larger region of suppressed recombination spanning two chromosomes. This process is analogous to the formation of neo-sex chromosomes and consistent with models of expanding regions of suppressed recombination. We propose that miniaturized queens, 16%-20% smaller than queens without 9r, could be incipient intraspecific social parasites

Detailed morphological descriptions of the immature stages of the ant parasite Microdon mutabilis (Diptera: Syrphidae: Microdontinae) and a discussion of its functional morphology, behaviour and host specificity. Corresponding author

The myrmecophilous immature stages of hover fl ies of the genus Microdon Meigen, 1803 (Diptera, Syrphidae) are still poorly known and only about 15 species were previously incompletely described and/or illustrated using light microscopy based on occasional fi ndings mainly of pupae and third instar larvae. The exceptional fi nding of a large number of second and third instar larvae and pupae (159 specimens) of Microdon mutabilis (Linnaeus, 1758) inside the nest of a new host species, Formica cunicularia Latreille,1798, enabled us to rear them and obtain a great number of eggs and fi rst instar larvae. We fi lmed and described the feeding behaviour and locomotion of these highly derived slug-like larvae. Combining light, fl uorescence and scanning electron (SEM) microscopy, we describe in detail and illustrate the external features of all the immature stages of M. mutabilis (eggs, larvae and pupae). Covering the entire chorion of the egg is a peculiar microsculpture composed of volcano-like processes. The three larval instars strongly differ from each other, especially at the level of the shape of the body, the posterior spiracular tubercle and the cephaloskeleton. SEM microscopy was used to describe in detail the microsculpture, sensorial structures, spiracles and cephalic appendages of larvae and pupae. Fluorescence microscopy was used to reveal the exceptional presence of resilin in the external layer of the posterior spiracular tubercle in fi rst instar larvae. The possible functional signifi cance of these structures is discussed

Early queen joining and long-term queen associations in polygyne colonies of an invasive wasp revealed by longitudinal genetic analysis.

Invasive social insects rank among the most damaging of terrestrial species. They are responsible for extensive damage and severely threaten the biodiversity of environments where they are introduced. Variation in colony social form commonly occurs in introduced populations of yellowjacket wasps (genus Vespula). In particular, invasive colonies may contain multiple queens (i.e., polygyne) and persist several years, while in the native range, the colonies are usually annual and harbor a single queen (i.e., monogyne). In this study, we used genome-wide loci obtained by double digest restriction site-associated DNA sequencing (RADseq) to investigate the genetic structure and queen turnover in colonies of the western yellowjacket, Vespula pensylvanica, in their introduced range in Hawaii. Of the 27 colonies monitored over four months (October-January), 19 were polygyne and already contained multiple queens on the first day of sampling. Contrary to previous speculation, this finding suggests that polygyny often arises early in the annual colony cycle, before the production of new queens in the fall. Furthermore, polygyne colonies exhibited a prolonged average lifespan relative to those headed by a single queen. As a result, there is no clear window during which colony eradication efforts would be more effective than upon first discovery. The relatedness among nestmate queens was slightly above zero, indicating that these colonies are generally composed of nonrelatives. The queen turnover within each colony was low, and we detected some full-sibling workers sampled up to four months apart. Finally, we did not detect any population structure among colonies, suggesting that queens disperse up to several kilometers. Taken together, our results provide the first insights into the requeening dynamics in this invasive and incipiently polygyne population and illuminate the early establishment of multiple long-lasting queens in these damaging colonies

Strange loves: a remarkable case of aberrant copulation in beetles (Coleoptera: Meloidae, Chrysomelidae)

A case of copulation between two mimic and repellent beetle species (a male of Timarcha fracassii, and a female of Meloe autumnalis), belonging to distinct families (Chrysomelidae, Meloidae), is recorded