Disentangling the effects of local resources, landscape heterogeneity and climatic seasonality on bee diversity and plant-pollinator networks in tropical highlands.

Land-use alteration and climate seasonality have profound effects on bee species diversity by influencing the availability of nesting and floral resources. Here, using twelve sites embedded in an agriculture-forest mosaic in the tropical highlands of Guatemala, we investigated the relative effects of climate seasonality and landscape heterogeneity on bee and floral-resource community structure and on their mutualistic network architecture. We found that climate seasonality affected bee diversity, which was higher in the wet season and associated positively with the availability of floral resources across both seasons. Bee community composition also differed between seasons and it was mainly driven by floral-resource richness and the proportion of agricultural, semi-natural and forest cover. In addition to the effects on bee diversity, climate seasonality also affected flower-bee visitation networks. We documented higher relative (null model corrected) nestedness in the dry season compared to the wet season. Niche partitioning as a result of competition for scarce resources in the dry season could be the process driving the differences in the network structure between seasons. Furthermore, relative nestedness was consistently smaller than zero, and relative modularity and specialization were consistently larger than zero in both seasons, suggesting the existence of isolated groups of interacting partners in all our flower-bee visitation networks. Our results highlight the effect of climatic seasonality and the importance of preserving local floral resources and natural heterogeneous habitats for the conservation of bee communities and their pollination services in tropical highlands.

Catálogo de las abejas del género Bombus Latreille, 1802 (Hymenoptera: Apoidea: Apidae) de Guatemala / Catalogue of the bees of the genus Bombus Latreille, 1802 (Hymenoptera: Apoidea: Apidae) in Guatemala

Este catálogo contiene un inventario actualizado de las especies del género Bombus que han sido citadas para Guatemala. Se presentan los datos taxonómicos, incluyendo sinonimias, de un total de 13 especies. Además, para cada especie se indica su distribución geográfica y las regiones bióticas de Guatemala en las que se ha recolectado. Este trabajo es la base para la posterior revisión del género Bombus en Guatemala.

This catalog contains an updated list of the species of the genus Bombus registered for Guatemala. Taxonomic data are presented for a total of 13 species, including synonyms and their geographical distribution, with emphasis in Guatemala. This work is the basis for the subsequent revision of the genus Bombus in Guatemala.

The subgenus Andrena (Micrandrena) (Hymenoptera: Andrenidae) in the Iberian Peninsula.

This work presents the results obtained after a revision of the current species of the subgenus Andrena (Micrandrena) Ashmead, 1899 that appear in the Iberian Peninsula. It provides a key to the species, diagnosis, biological data, and comments about the 19 species and 5 subspecies. Additionally, it includes a redescription of five species because their original descriptions were inadequate. Newly reported for the Iberian Peninsula are Andrena floricola Eversmann, 1852 and Andrena strohmella Stöckhert, 1928. This study is the first contribution to resolve certain taxonomic problems in the subgenus Andrena (Micrandrena); however, the use of additional tools like morphometric and molecular characters are recommended in the future to confirm the taxonomic status of Andrena spreta Pérez, 1895. 

Analysis of the diversity of Megachilidae bees on the northern subplateau of the Iberian Peninsula.

In the western Mediterranean, 772 species of bees in the family Megachilidae have been reported. Special emphasis has been placed on the Iberian Peninsula, where to date 218 species are known. However, few intensive studies providing information about communities of Megachilidae have been carried out. Two earlier works cite 70 species; almost one third of those known on the Peninsula. With an aim of gaining insight into the structure of the communities of Megachilidae and the factors influencing them, an analysis was made of the alpha and beta diversity of different localities in the northern subplateau. Malaise traps (black and white) were used, and 559 specimens belonging to 55 species were identified of which most exhibited a nest-holder-type nesting habit. Abundance and richness were higher for white traps, although a considerable degree of complementarity was observed with the black traps. In the study zone, diversity can be considered medium-high with a phylogenetic diversity corresponding to stable populations. Regarding the composition of the Megachilidae communities, the influence of the landscape structure, of the microhabitat, and of the colour of the trap used to collect the specimens was detected. The following are recommended: (1) the use of both black and white traps, since they show high complementarity and offer different information about community structure, (2) homogenization of the samples in comparisons among communities, owing to the influence of the color of the trap, which masks the importance of ecological factors in community structuring, and (3) the collection of samples from at least two years previous, in view of the elevated "replacement" of species observed with species richness estimators.

Caracterización fisicoquímica y antimicrobiana de la miel de nueve especies de abejas sin aguijón (Meliponini) de Guatemala / Physicochemical and antimicrobial characterization of nine stingless bees (Meliponini) honey from Guatemala / Caracterização fisicoquímica e antimicrobiana do mel de nove especies de abelhas sem ferrão (Meliponini) de Guatemala

La miel de meliponinos es reconocida popularmente en Latinoamérica por sus propiedades terapéuticas. En Guatemala, unas 13 especies son criadas artesanalmente para la obtención de miel. Debido al reciente interés en la utilización de la miel de meliponinos en Guatemala y a su comercialización, se hace necesario conocer las características fisicoquímicas y validar el uso terapéutico de la misma. En el presente trabajo se realizó una caracterización fisicoquímica y antibacteriana de la miel producida en Guatemala de nueve especies de meliponinos: Geotrigona acapulconis (Strand, 1919); Melipona beecheii Bennett, 1831; Melipona solani Cockerell, 1912; Melipona aff. yucatanica; Nannotrigona perilampoides Cresson, 1878; Plebeia sp.; Scaptotrigona mexicana Guérin, 1845; Scaptotrigona pectoralis Dalla Torre, 1896; y Tetragonisca angustula (Latreille, 1811). Los valores promedio obtenidos en 18 muestras fueron: humedad 21,55g/100g de miel; acidez 22,45meq/kg; cenizas 0,29g/100g; hidroximetilfurfural 0,23mg/kg; actividad de la diastasa 10,94DN; y pH 3,89. Se evaluó la actividad antibacteriana frente a ocho microorganismos, determinando una concentración inhibitoria mínima de 2,5 a 10% (v/v). Se realizó un análisis preliminar de tipos polínicos que permitió identificar la presencia de 21 familias vegetales visitadas por los meliponinos en Guatemala, donde la miel de T. angustula presentó la mayor diversidad. Este trabajo es el primer aporte al conocimiento sobre la composición fisicoquímica y antibacteriana de las mieles de nueve especies de meliponinos en este país.

The honey of stingless bees is popularly known in Latin America for its therapeutic properties. In Guatemala some 13 species are traditionally bred to obtain honey. Due to the recent interest and trading of meliponine honey, it is necessary to know the physicochemical properties and to validate its therapeutic use. The antimicrobial activity, the physicochemical composition and the botanical origin of the honey produced by nine species of stingless bees from Guatemala is reported. The species were Geotrigona acapulconis (Strand, 1919); Melipona beecheii Bennett, 1831; Melipona solani Cockerell, 1912; Melipona aff. yucatanica; Nannotrigona perilampoides Cresson, 1878; Plebeia sp.; Scaptotrigona mexicana Guérin, 1845; Scaptotrigona pectoralis Dalla Torre, 1896; and Tetragonisca angustula (Latreille, 1811). The average values obtained in 18 samples were: Moisture 21.55g for 100g of honey, acidity 22.45meq/100g, ash 0.29g/100g, hidroximetilfurfural 0.23mg/kg, diastase activity 10.94 N, and pH 3.89. The antibacterial activity of the honey against eight microorganisms was determined; the minimum inhibitory concentration was found to be of 2.5 to 10% (v/v). A preliminary palynological analysis permitted the identification of 21 vegetal families in the honey samples of Guatemala, among which the honey of T. angustula presented the greatest diversity. This work is the first contribution about the composition of honey from nine species of meliponini in the country.

O mel de meliponíneos é reconhecido popularmente na América Latina por suas propriedades terapêuticas. Na Guatemala, umas 13 espécies são criadas artesanalmente para a obtenção de mel. Devido ao recente interesse na utilização do mel de meliponíneos na Guatemala e a sua comercialização, se faz necessário conhecer as características físico-químicas e validar o uso terapêutico da mesma. No presente trabalho se realizou uma caracterização físico-química e antibacteriana do mel produzido na Guatemala de nove espécies de meliponíneos: Geotrigona acapulconis (Strand, 1919); Melipona beecheii Bennett, 1831; Melipona solani Cockerell, 1912; Melipona aff. yucatanica; Nannotrigona perilampoides Cresson, 1878; Plebeia sp.; Scaptotrigona mexicana Guérin, 1845; Scaptotrigona pectoralis Dalla Torre, 1896; e Tetragonisca angustula (Latreille, 1811). Os valores médios obtidos em 18 amostras foram: umidade 21,55g/100 g de mel; acidez 22,45meq/kg; cinzas 0,29g/100g; hidroximetilfurfural 0,23mg/kg; atividade da diastasa 10,94DN; y pH 3,89. Avaliou-se a atividade antibacteriana frente a oito microorganismos, determinando uma concentração inibitória mínima de 2,5 a 10% (v/v). A análise preliminar de tipos polínicos permitiu identificar a presença de 21 famílias vegetais visitadas pelos meliponíneos na Guatemala, onde o mel de T. angustula apresentou a maior diversidade. Este trabalho é o primeiro aporte ao conhecimento sobre a composição físico-química e antibacteriana do mel de noves espécies de meliponíneos neste país.