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The flowers of the species of Malpighiaceae in the Neotropical Region are relatively uniform in their morphology due to their dependence on oil-collecting bees as their main pollinators. However, many species of the genus Galphimia seem to have acquired a different floral syndrome, lacking markedly zygomorphic flowers and developed elaiophores in the calyx. Likewise, these species present anthers with great development, probably in response to the selection of pollinators that collect pollen. Galphimia australis incorporated some of these traits but also retained some residual characteristics typical of species pollinated by oil bees. This leads to many questions on how these flowers ensure their pollination. Inquiring about the reduction or modification of these characteristics allows us to understand how G. australis achieves a different pollination syndrome. In this research, we carry out a detailed morphological and anatomical study of the flowers and pollen grain devolvement of G. australis and floral visitors were observed and captured. Results were analyzed in order to determine how this species changed from the oil-floral syndrome, typical of neotropical Malpighiaceae, to one syndrome with pollen as the main reward.

Fil: Marrero, Hugo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina

A recent (March 2006) field survey of plant-pollinator interactions in North Patagonia, Argentina, revealed the presence of Bombus terrestris as flower visitors to several plant species in a natural environment. This is the first record of this invasive bumblebee in Argentina. The available evidence suggests that B. terrestris entered Argentina from Chile, where it was introduced in 1998, through low-altitude passes across the Andes.

The flesh fly community was surveyed on the shoreline of Río de la Plata at an ecological reserve whose western border directly abuts downtown eastern Buenos Aires. Samples were taken at monthly intervals from September 2004 to August 2005. To attract the flies, dog faeces and rotten cow liver were used as bait. Overall number, species composition and sex ratio were referred to each chosen bait. Of the thirteen species captured during the sampling period, Helicobia aurescens (Townsend), Oxysarcodexia culmiforceps Dodge, Oxysarcodexia marina (Hall), Oxysarcodexia thornax (Walker), Sarcophaga (Lipoptilocnema) koehleri (Blanchard), S. (L.) lanei (Townsend) and Tricharaea (Sarcophagula) occidua (Fabricius) were recorded for the first time in Buenos Aires city. Regardless of species composition, higher number of flies were obtained on faeces. Tricharaea (S.) occidua, was highly dominant (78,35%) followed in abundance by Oxysarcodexia varia (7,82%), both species showing a strong preference for dog faeces. Microcerella muehni and Oxysarcodexia paulistanensis did not show any preference on either bait. Sex ratio was male biased for O. varia, while females were dominant for O. paulistanensis and T. (S.) occidua, and no differences were found for M. muehni. Bait's preference and sex ratio could not be estimated for the remaining species due to their low abundance.

Sunflower (Helianthus annuus) is an oilseed crop pollinated by Apis mellifera L. and other diurnal bees in different regions of the world. However, their flowers are also visited by insects active at night. During three agricultural years, the diversity of nocturnal visitors to sunflower heads was assessed in five different sites in Argentina. The foraging behavior of the main visitors as well as the stigmatic receptivity variations along the day were also studied in order to determine whether or not these visitors contribute to pollination. At least 67 species or morpho-species belonging to four nocturnal visitor orders were recorded. The richest and most abundant order was Lepidoptera (44 species or morpho-species, five families), followed by Coleoptera (18 species or morpho-species, nine families), Orthoptera (three morpho-species, one family) and Blattaria (two species, one family). Lepidopterans foraged exclusively for nectar while species in other orders consumed pollen and/or floral parts. However, stigma receptivity was greater during the day, peaking at midday (12:00 - 14:00). Unexpectedly, moth species widely outnumbered bee species as sunflower visitors. Since moths potentially transfer pollen at a time of the day when stigmas are least receptive, it is unlikely that they do effectively pollinate sunflowers.Original Abstract: El girasol (Helianthus annuus) es un cultivo oleaginoso, polinizado por Apis mellifera L. y otras abejas en distintas regiones del mundo. Sin embargo, sus flores tambien son visitadas por insectos de actividad nocturna. Durante tres campanas agrfcolas, se determino la diversidad de los visitantes nocturnos de capftulos de girasol, en cinco sitios de Argentina. Tambien se estudio el comportamiento de forrajeo de los principales visitantes y la variacion de la receptividad estigmatica a lo largo del dfa, con el fin de establecer si estos visitantes contribuyen a la polinizacion. Al menos 67 especies o morfoespecies pertenecientes a cuatro ordenes de visitantes nocturnos fueron colectadas. El orden mas rico y abundante fue Lepidoptera (44 especies o morfoespecies, cinco familias), seguido por Coleoptera (18 especies o morfoespecies, nueve familias), Orthoptera (tres morfoespecies, una familia) y Blattaria (dos especies, una familia). Los lepidopteros forrajearon exclusivamente por nectar, mientras que los individuos de los demas ordenes consumieron polen y/o partes florales. El estigma se encontro receptivo durante las horas de luz, con una receptividad maxima al mediodia (12:00 -14:00). Llamativamente, las flores del girasol son visitadas por mayor numero de polillas que de abejas. Debido a que las polillas consumen nectar y potencialmente transportan polen entre flores, en un momento del dia en que los estigmas se encuentran menos receptivos, es improbable que polinicen efectivamente el cultivo.

Sunflower (Helianthus annuus L.) is an important oilseed crop in Argentina. During three agricultural years, the diversity and abundance of diurnal floral visitors of sunflower heads were determined in eight sites spanning much of this crop's cultivation area in Argentina. Seventy-six morpho-species of floral visitors, belonging to eight orders, were captured on sunflower. The principal order was Hymenoptera, with 37 species or morpho-species, of which 32 were bees (Apoidea). The most represented bee families were Apidae (13), Megachilidae (11) and Halictidae (7). The domestic bee (Apis mellifera L.) accounted for 93% of the visits. Floral visitor composition did not show an identifiable variation pattern either throughout the day or with respect to the distance to the edge of the crop, but varied among sites. It is concluded that the domestic bee is the main sunflower pollinator in Argentina, although several native bee species (Melissodes tintinnans (Holmberg), M. rufithorax Brethes, Melissoptila tandilensis Holmberg, and Megachile spp.) could be considered as potential crop pollinators.Original Abstract: El girasol (Helianthus annuus L.) es un importante cultivo oleaginoso en la Argentina. Durante tres campanas agricolas, se determinaron la diversidad y la abundancia del elenco de los visitantes florales diurnos de capitulos de girasol, en ocho sitios que cubren gran parte del area cultivada en Argentina. Setenta y seis morfo-especies de visitantes florales, pertenecientes a ocho ordenes, fueron capturados sobre capitulos de este cultivo. El principal orden fue Hymenoptera, con 37 especies o morfo-especies, de las cuales 32 fueron abejas (Apoidea). Las familias de abejas mas representadas fueron Apidae (13), Megachilidae (11) y Halictidae (7). La abeja domestica (Apis mellifera L.) realizo el 93% de las visitas. La composicion del elenco de visitantes no mostro un patron de variacion identificable a lo largo del dia, ni con respecto a la distancia al borde del cultivo, pero vario entre sitios de muestreo. Se concluye que la abeja domestica es el principal polinizador del girasol en la Argentina, aunque varias especies nativas de abejas (Melissodes tintinnans (Holmberg), M. rufithorax Brethes, Melissoptila tandilensis Holmberg, y Megachile spp.) podrfan ser consideradas como potenciales polinizadores del cultivo.

Urbanization is one of the main processes generating large changes on the Earth's surface. The remaining green spaces within cities can be of utmost importance for pollinator conservation. Through a systematic literature review, we evaluate how the connectivity of urban green areas (parks, gardens, squares, among others) in different cities can affect the richness and abundance of pollinators. We utilize a connectivity metric using satellite images corresponding to 241 urban green areas obtained from 20 published works. The green areas were classified in urban, peri-urban and non-urban according to their percentage of impervious surface estimated in each image. The metric relates the connectivity of green areas contained within images with a radius of 500 m immersed within a city. Our study shows the richness and abundance of pollinators is positively correlated with the connectivity of green areas in sites with different degrees of urbanization, mainly in urban and peri-urban sites. Our results emphasize the importance of green spaces to maintain the pollinator’s community in cities, and suggest that proper design and/or management could improve conditions for these important insects.

Interleukin 10 (IL-10) is an antiinflammatory cytokine, but also promotes B cell responses and plays a pathogenic role in systemic lupus erythematosus (SLE). CD4⁺CCR6⁺IL-7R⁺T cells from human tonsils produced IL-10 following stimulation by naïve B cells, which promoted B cell immunoglobulin G (IgG) production. These tonsillar CCR6⁺B helper T cells were phenotypically distinct from follicular helper T (TFH) cells and lacked BCL6 expression. In peripheral blood, a CCR6⁺T cell population with similar characteristics was identified, which lacked Th17- and TFH-associated gene signatures and differentiation-associated surface markers. CD4⁺CCR6⁺T cells expressing IL-10, but not IL-17, were also detectable in the spleens of cytokine reporter mice. They provided help for IgG production in vivo, and expanded systemically in pristane-induced lupus-like disease. In SLE patients, CD4⁺CCR6⁺IL-7R⁺T cells were associated with the presence of pathogenic anti-dsDNA (double-stranded DNA) antibodies, and provided spontaneous help for autoantibody production ex vivo. Strikingly, IL-10–producing CCR6⁺T cells were highly abundant in lymph nodes of SLE patients, and colocalized with B cells at the margins of follicles. In conclusion, we identified a previously uncharacterized population of extrafollicular B helper T cells, which produced IL-10 and could play a prominent pathogenic role in SLE.