Superparasitism and host discrimination by Neodohrniphora elongata (Diptera: Phoridae), a parasitoid of the leaf-cutting ant Atta sexdens rubropilosa (Hymenoptera: Formicidae)

The leaf-cutting ant Atta sexdens rubropilosa Forel is parasitized by several species of Phoridae flies, one of which is Neodohrniphora elongata Brown. The female of this fly oviposits inside the head of larger workers of the Atta colony, emerging only one fly from each cephalic capsule. The objective of this study was to investigate the occurrence of superparasitism by.N. elongata on workers of A. sexdens rubropilosa in the laboratory and to describe if the female of this parasitoid is able to discriminate between non-parasitized and previously parasitized workers by itself and between non-parasitized and previously parasitized workers by another female of the same species. The tests were conducted in a glass observation chamber where 15 parasitized and 15 non-parasitized workers and one fly were released at a time. The flies laid eggs preferentially in non-parasitized workers rather than workers parasitized by themselves (n=11) or parasitized by other females (n=18). In both cases females of N. elongata were able to discriminate the parasitized host, rejecting most of them, but did not avoid superparasitism. Based on the high indices of superparasitism found (29.4% ofselfsuperparasitismand49.5%of conspecific superparasitism), the process of host discrimination by N. elongata seems to be of little efficiency at least under experimental conditions

A fauna de abelhas silvestres na Rppn Canguçu - Pium-To (Hymenoptera, Anthophila): dados preliminares i / The wild bees fauna in the Canguçu Rppn - Pium-To (Hymenoptera, Anthophila): preliminary data i

As abelhas são, reconhecidamente, o grupo principal de polinizadores em paisagens naturais e agrícolas, sendo a polinização um dos fenômenos biológicos chaves para a conservação ambiental, reprodução vegetal e produção de alimentos em todo o mundo. O reconhecimento da identidade taxonômica das espécies de abelhas figura como um dos pré-requisitos básicos para ações de uso sustentado e conservação deste importante grupo de polinizadores.  Neste trabalho, foram inventariadas as espécies de abelhas silvestres do bioma Cerrado-Floresta Amazônica, na Reserva Particular do Patrimônio Natural Canguçu (RPPN), analisando a riqueza e abundância de abelhas neste ambiente. Como metodologia de inventário, foram utilizados cinco métodos de captura das abelhas (armadilha malaise, coleta ativa com rede entomológica, armadilhas coloridas de água (ARCA's ou pantraps), armadilhas pet com substância açucarada e armadilhas de cheiro, as quais foram contabilizadas e preparadas para identificação, segundo técnicas padrões de estudo de insetos, com deposição dos exemplares coletados nos acervos da Coleção Entomológica da Universidade Federal do Tocantins (UFT) e do Museu de História Natural da Bahia, na Universidade Federal da Bahia (MHNBA- UFBA). As coletas foram realizadas em três trilhas dentro da área do Canguçu, tendo sido identificados 147 indivíduos, correspondendo a 27 espécies distribuídas em 7 tribos e 15 gêneros, com destaque para as famílias Apidae e Halictidae, e maior pico amostral ocorrendo em Setembro/18. A espécie mais abundante localmente foi a Trigona pallens (Fabricius, 1798) (Apidae, Meliponini), tendo sido coletadas abelhas do gênero Melipona (Apidae, Meliponini) e também do gênero Augochlorodes (Halictidae). Embora os dados apresentados aqui sejam preliminares, a região apresentou grande diversidade de espécies, demonstrando a necessidade de novos estudos para conhecimento da fauna de abelhas local, com referência para a importância da conservação ambiental para a manutenção da biodiversidade de abelhas e vice-versa.

Population-based seroprevalence of SARS-CoV-2 and the herd immunity threshold in Maranhão

OBJECTIVE: To estimate the seroprevalence of SARS-CoV-2 in the state of Maranhão, Brazil. METHODS: A population-based household survey was performed, from July 27, 2020 to August 8, 2020. The estimates considered clustering, stratification and non-response. Qualitative detection of IgM and IgG antibodies was performed in a fully-automated Elecsys® Anti-SARS-CoV-2 electrochemiluminescence immunoassay on the Cobas® e601 analyzer (Roche Diagnostics). RESULTS: In total, 3,156 individuals were interviewed. Seroprevalence of total antibodies against SARS-CoV-2 was 40.4% (95%CI 35.6-45.3). Population adherence to non-pharmaceutical interventions was higher at the beginning of the pandemic than in the last month. SARS-CoV-2 infection rates were significantly lower among mask wearers and among those who maintained social and physical distancing in the last month compared to their counterparts. Among the infected, 26.0% were asymptomatic. The infection fatality rate (IFR) was 0.14%, higher for men and older adults. The IFR based on excess deaths was 0.28%. The ratio of estimated infections to reported cases was 22.2. CONCLUSIONS: To the best of our knowledge, the seroprevalence of SARS-CoV-2 estimated in this population-based survey is one of the highest reported. The local herd immunity threshold may have been reached or might be reached soon.OBJECTIVE: To estimate the seroprevalence of SARS-CoV-2 in the state of Maranhão, Brazil. METHODS: A population-based household survey was performed, from July 27, 2020 to August 8, 2020. The estimates considered clustering, stratification and non-response. Qualitative detection of IgM and IgG antibodies was performed in a fully-automated Elecsys® Anti-SARS-CoV-2 electrochemiluminescence immunoassay on the Cobas® e601 analyzer (Roche Diagnostics). RESULTS: In total, 3,156 individuals were interviewed. Seroprevalence of total antibodies against SARS-CoV-2 was 40.4% (95%CI 35.6-45.3). Population adherence to non-pharmaceutical interventions was higher at the beginning of the pandemic than in the last month. SARS-CoV-2 infection rates were significantly lower among mask wearers and among those who maintained social and physical distancing in the last month compared to their counterparts. Among the infected, 26.0% were asymptomatic. The infection fatality rate (IFR) was 0.14%, higher for men and older adults. The IFR based on excess deaths was 0.28%. The ratio of estimated infections to reported cases was 22.2. CONCLUSIONS: To the best of our knowledge, the seroprevalence of SARS-CoV-2 estimated in this population-based survey is one of the highest reported. The local herd immunity threshold may have been reached or might be reached soon

New species of Eibesfeldtphora Disney (Diptera: Phoridae) and a new key to the genus

Two new species of parasitoids, Eibesfeldtphora trifurcata and Eibesfeldtphora inornata, are described. Both species were collected in Brazil. A new key is provided and illustrated for the twenty one known species. Copyright © 2014 Magnolia Press