A new species of <i>Trigonisca</i> and new records of stingless bees for Argentina (Hymenoptera: Apidae)

Una especie nueva de Trigonisca es descrita para el Noroeste de Argentina, Trigonisca sachamiski sp. nov., la cual se distribuye en las provincias de Salta y Jujuy. Se presentan también mapas de distribución, notas comparativas y sinopsis de las especies de Nannotrigona y Lestrimelitta que están presentes en la Argentina. Nannotrigona melanocera y Lestrimelitta rufa son reportadas por primera vez para la Argentina y se presenta una clave para reconocer las cuatro especies registradas en la Argentina de Lestrimelitta.A new species of Trigonisca is described for northwestern Argentina, Trigonisca sachamiski sp. nov., of Salta and Jujuy provinces. Distribution maps, comparative notes and a synopsis of Nannotrigona and Lestrimelitta present in Argentina are also given. Nannotrigona melanocera and Lestrimelitta rufa are reported for the first time in Argentina and key is provided to four Argentinian species of Lestrimelitta.Facultad de Ciencias Naturales y Muse

Eating with the enemy?: mimic complex between a stingless bee and assassin bugs

In this study, we record for the first time the genus Notocyrtus (Heteroptera, Reduviidae) from Argentina based on three species: Notocyrtus dorsalis (Gray), Notocyrtus dispersus Carvalho & Costa, and Notocyrtus foveatus Stål. We also describe and illustrate a mimetic complex comprising the three Notocyrtus species and Tetragona clavipes (Fabricius) (Apidae, Meliponini), that were collected on Bahuinia forficata Link (Leguminosae: Caesalpinioideae). We include biological comments on the plant-reduvid-bee interaction and hypothesize about the functionality of the mimetic complex described.Facultad de Ciencias Naturales y Muse

Multilevel Multiphase Feedforward Space-Vector Modulation Technique

Multiphase converters have been applied to an increasing number of industrial applications in recent years. On the other hand, multilevel converters have become a mature technology mainly in medium- and high-power applications. One of the problems of multilevel converters is the dc voltage unbalance of the dc bus. Depending on the loading conditions and the number of levels of the converter, oscillations appear in the dc voltages of the dc link. This paper presents a feedforward modulation technique for multilevel multiphase converters that reduces the distortion under balanced or unbalanced dc conditions. The proposed modulation method can be applied to any multilevel-converter topology with any number of levels and phases. Experimental results are shown in order to validate the proposed feedforward modulation technique.Ministerio de Ciencia e Innovación DPI2009-07004Ministerio de Eduación y Ciencia TEC2007-6187

The first cases of gynandromorphism in oil‑collecting bees (Hymenoptera, Apidae: Centridini, Tapinotaspidini)

Here we provide descriptions of gynandromorphs of two species oil-collecting bees: Lophopedia nigrispinis and Epicharis iheringii, both with partial bilateral phenotypic asymmetry. The bees have a female phenotype predominantly on mesosoma and metasoma. The specimen of L. nigrispinis has distinct characteristics on legs, suggesting a mosaic pattern of gynandromorphism. The pollen and oil loads on legs suggest that the bee was foraging normally. The gynander specimen of E. iheringii has mostly a female phenotype, except for head, with right half female type and left half male type. The specimen of L. nigrispinis was collected foraging on flowers of Bidens sp. at Parque Nacional Iguazú, Argentina with loads of pollen on legs suggesting it was reproductive and was provisioning a nest. The specimen of Epicharis iheriingi has no evidence of any oil or pollen collection, despite its mostly female phenotype.Facultad de Ciencias Naturales y Muse

Temporal drop of genetic diversity in <i>Bombus pauloensis</i>

Bumblebees are economically important insects which perform essential pollination tasks in natural and managed ecosystems. Recent research studying Neotropical bumblebee species in Brazil showed a clear decrease in genetic diversity over time in Bombus pauloensis. A new temporal assessment of genetic diversity is needed to know whether this was a location-specific result, or a more general phenomenon. This knowledge is essential to be able to prioritize conservation and management needs. Here, the genetic variability of B. pauloensis populations in Argentina was investigated over time using museum collection specimens from 1933 to 2016, and compared with reanalyzed data from Brazilian populations. Furthermore, specific time series were made for two Argentinean locations, Candelaria and La Plata, and compared with the time series of Porto Alegre (Brazil). All collected specimens were genotyped with 16 microsatellite loci to estimate genetic diversity parameters. Our results showed no drop in either allelic richness or expected heterozygosity over all Argentinean populations. However, a clear drop in genetic diversity was observed in two out of three location-specific time series. This loss of diversity will have negative impacts on population survival, especially over longer periods of time. Furthermore, the use and release of mass-reared specimens of B. pauloensis, which may be inbred and specifically selected for certain commercial but non-adaptive traits, could further diminish the genetic pool. Thus, our result implies the urgent need for regional conservation policies of B. pauloensis in South Brazil and North Argentina.Facultad de Ciencias Naturales y MuseoCentro de Estudios Parasitológicos y de Vectore

Shock obstructivo secundario a tromboembolismo pulmonar y neumotórax simultáneos: utilidad de la ecografía clínica

Cardiac arrest is a diagnostic and therapeutic challenge in emergency departments. Bedside clinical ultrasonography can decisively help the emergency physician in decision making. We report a case of a patient who evolved to pulseless electrical activity presenting a massive pulmonary embolism and a pneumothorax simultaneously, both potentially responsible for this consequence. Clinical ultrasound performed during resuscitation manoeuvres helped to discern which pathology was responsible and allowed to establish a targeted treatment that contributed to the favourable outcome of the patient.El paro cardíaco supone un reto diagnóstico y terapéutico en los servicios de Urgencias. La ecografía clínica a pie de cama puede ayudar al urgenciólogo en la toma de decisiones de manera decisiva. Presentamos el caso de una paciente que evoluciona a actividad eléctrica sin pulso presentando un tromboembolismo pulmonar masivo y un neumotórax simultáneos, ambos potencialmente responsables de dicho desenlace. La ecografía clínica realizada durante las maniobras de reanimación permitió discernir qué patología era la responsable y establecer un tratamiento dirigido que contribuyó a la evolución favorable de la paciente

Bees associated to eggplant crop (Solanum melongena L., Solanaceae) in greenhouse in the horticulture zone of La Plata, Buenos Aires, Argentina

El cultivo de berenjena tiene en muchos países gran importancia económica, por este motivo actualmente se encuentra en amplia expansión a nivel mundial. En este trabajo se estudiaron las abejas asociadas a este cultivo producido en invernadero en la zona hortícola de La Plata, Buenos Aires, Argentina. Se reconocieron un total de 21 especies de abejas asociadas al cultivo; siendo la familia Halictidae las más representativa con 15 especies seguida de Apidae con cuatro. El pico de las visitas florales se registró en el horario matinal entre las 08:30hs y 11:30hs, coincidiendo con el comienzo de la antesis y dehiscencia de las anteras. Concluimos que las especies Bombus atratus y Xylocopa augusti pueden considerarse como las especies con mayor potencial para la polinización dirigida de este cultivo en invernadero.The eggplant crop, currently in expansion, has great economic importance to many countries in the world. Bees associated with this crop which has grown up in greenhouse in the horticulture zone of La Plata, Buenos Aires, Argentina were sampling. Twenty one species of bees were recorded within the crop, and the family Halictidae was the most representative with 15 species followed by Apidae with four species. The greatest number of visits of bees were recorded in the morning between 08:30hs and 11:30hs coinciding with beginning of the anthesis and dehiscence of anthers. We conclude that the species Bombus atratus and Xylocopa agusti could be considered as potential crop pollinators due to its large size, buzz pollination, easy breeding and use within the greenhouse crops.Facultad de Ciencias Agrarias y Forestale

Detection of honey bee viruses in Argentinian stingless bees (Hymenoptera: Apidae)

The Meliponini is a eusocial group of bees tropically distributed. In Argentina, 37 species have been recorded, mostly in Misiones province. They use a great variety of sites to build their nests including tree hollows, cavities formed in rocks, human constructions or underground spaces. Numerous natural enemies are associated with stingless bees, including viruses. Until now, some viruses present in honey bees and related to the colony collapse disorder (CCD), have been found in several wild bees around the world. Here, we have studied the presence of honey bee viruses in stingless bees from different locations of Misiones province, Argentina. On this research, 73 samples of ten workers belonging to 12 species of stingless bees and feral honey bees, have been analyzed. Our results confirm the presence of three viruses: ABPV, IAPV and DWV Type A in four species of stingless bees and feral honey bees. More studies are required to establish if ABPV, IAPV and DWV are natural pathogens of stingless bees that have been spilled over to honey bees, or were transmitted by Apis mellifera to stingless bees.Facultad de Ciencias Naturales y MuseoFacultad de Ciencias Veterinaria

Bees associated to eggplant crop (Solanum melongena L., Solanaceae) in greenhouse in the horticulture zone of La Plata, Buenos Aires, Argentina

El cultivo de berenjena tiene en muchos países gran importancia económica, por este motivo actualmente se encuentra en amplia expansión a nivel mundial. En este trabajo se estudiaron las abejas asociadas a este cultivo producido en invernadero en la zona hortícola de La Plata, Buenos Aires, Argentina. Se reconocieron un total de 21 especies de abejas asociadas al cultivo; siendo la familia Halictidae las más representativa con 15 especies seguida de Apidae con cuatro. El pico de las visitas florales se registró en el horario matinal entre las 08:30hs y 11:30hs, coincidiendo con el comienzo de la antesis y dehiscencia de las anteras. Concluimos que las especies Bombus atratus y Xylocopa augusti pueden considerarse como las especies con mayor potencial para la polinización dirigida de este cultivo en invernadero.The eggplant crop, currently in expansion, has great economic importance to many countries in the world. Bees associated with this crop which has grown up in greenhouse in the horticulture zone of La Plata, Buenos Aires, Argentina were sampling. Twenty one species of bees were recorded within the crop, and the family Halictidae was the most representative with 15 species followed by Apidae with four species. The greatest number of visits of bees were recorded in the morning between 08:30hs and 11:30hs coinciding with beginning of the anthesis and dehiscence of anthers. We conclude that the species Bombus atratus and Xylocopa agusti could be considered as potential crop pollinators due to its large size, buzz pollination, easy breeding and use within the greenhouse crops.Facultad de Ciencias Agrarias y Forestale

Bees associated to eggplant crop (Solanum melongena L., Solanaceae) in greenhouse in the horticulture zone of La Plata, Buenos Aires, Argentina

El cultivo de berenjena tiene en muchos países gran importancia económica, por este motivo actualmente se encuentra en amplia expansión a nivel mundial. En este trabajo se estudiaron las abejas asociadas a este cultivo producido en invernadero en la zona hortícola de La Plata, Buenos Aires, Argentina. Se reconocieron un total de 21 especies de abejas asociadas al cultivo; siendo la familia Halictidae las más representativa con 15 especies seguida de Apidae con cuatro. El pico de las visitas florales se registró en el horario matinal entre las 08:30hs y 11:30hs, coincidiendo con el comienzo de la antesis y dehiscencia de las anteras. Concluimos que las especies Bombus atratus y Xylocopa augusti pueden considerarse como las especies con mayor potencial para la polinización dirigida de este cultivo en invernadero.The eggplant crop, currently in expansion, has great economic importance to many countries in the world. Bees associated with this crop which has grown up in greenhouse in the horticulture zone of La Plata, Buenos Aires, Argentina were sampling. Twenty one species of bees were recorded within the crop, and the family Halictidae was the most representative with 15 species followed by Apidae with four species. The greatest number of visits of bees were recorded in the morning between 08:30hs and 11:30hs coinciding with beginning of the anthesis and dehiscence of anthers. We conclude that the species Bombus atratus and Xylocopa agusti could be considered as potential crop pollinators due to its large size, buzz pollination, easy breeding and use within the greenhouse crops.Facultad de Ciencias Agrarias y Forestale