127 research outputs found
A synopsis of success: honey bees out of Africa
Fantástico como categoria estética: Diferenças entre os monstros de Ana Teresa Pereira e LÃdia Jorg
Especies nuevas y filogenia de las abejas de fuego, oxytrigona (hymenoptera: apidae, meliponini)
We describe and illustrate three new species from Central America and northern South America, present descriptions for previously unknown males and queens, and explore the internal phylogeny of Oxytrigona. Oxytrigona chocoana sp. nov., the sister species of O. daemoniaca, is from the Chocó biogeographic region; O. huaoranii sp. nov., and O. isthmina sp. nov., from the Eastern Andes of Ecuador and Darién (Panamá), are much smaller than their sister species, O. mellicolor. Oxytrigona huaoranii exhibits unusual characters including a short fore femur with carinate inferior margin, and  striated basal propodeum. The male of O. isthmina primarily differs from O. mellicolor in having genitalia with an apically enlarged and strongly bent gonostylus. We also described the males of O. daemoniaca and O. mediorufa, and the male and queen of O. mellicolor. The taxonomic status O. mediorufa is revised; as here understood, this species is distributed only from Mexico to El Salvador. We obtained a single tree for Oxytrigona in a cladistic analysis of 18 morphological and five body coloration characters, which did not support the monophyly of the mulfordi and tataira groups. We also found variation in the gradular and distal margin shapes of the worker sixth sternum, which were useful in the taxonomic analysis. Such characters have not yet been used in the systematics of Meliponini, and we hope to draw more attention to and encourage future phylogenetic studies using these characters. We also present an identification key for the species.Describimos e ilustramos tres especies nuevas de Oxytrigona de Centroamérica y norte de Suramérica, presentamos descripciones de machos y reinas previamente desconocidos, y exploramos la filogenia interna del género. Oxytrigona chocoana sp. nov., del Chocó biogeográfico, es la especie hermana de O. daemoniaca; O. huaoranii sp. nov. y O. isthmina sp. nov., del oriente de los Andes ecuatorianos y del Darién panameño, son mucho más pequeñas que su especie hermana, O. mellicolor. Oxytrigona huaoranii presenta caracteres inusuales tales como el fémur anterior corto, con el margen inferior fuertemente carenado, y el área basal del propódeo estriada. El macho de O. isthmina se diferencia principalmente de O. mellicolor por el gonostilo de la genitalia mucho más curvo y ensanchado apicalmente. También describimos los machos de O. daemoniaca y O. medioru f a, y el macho y la reina de O. mellicolor. El estatus taxonómico de O. medioru f a es revisado; según como la entendemos en este trabajo, esta especie se encuentra únicamente desde México hasta El Salvador. Un solo árbol fue obtenido para las especies de Oxytrigona, a partir del análisis cladÃstico de 18 caracteres morfológicos y cinco de coloración del cuerpo, el cual no apoya la monofilia de los grupos m u l f o rdi y tataira. Las variaciones encontradas en la forma del grádulo y del m a rgen distal del sexto esterno de la obrera, fueron útiles en el análisis taxonómico. Estos caracteres no han sido usados en la sistemática de Meliponini, y esperamos llamar la atención y promover su uso en futuros análisis filogenéticos. También presentamos una clave para la identificación de las especies
Trigona corvina
We found that the nest of Trigona corvina (Apidae; Meliponini) consists mainly of pollen exines from bee excrement, forming a scutellum shield encasing the colony. A 20-year-old nest (1980–2000) from a lowland Panama forested habitat was sawed in half longitudinally, and a 95 cm transect was systematically sampled each 5 cm. Samples subjected to detailed pollen analysis held 72 botanical species belonging to 65 genera in 41 families. Over 90% of scutellum pollen volume was Cecropiaceae and Arecaceae, among >1013 grains. Potentially the oldest samples, in the middle of the nest, indicate that Mimosoideae, Euphorbiaceae, and Bombacaceae (now Malvaceae) were lost when Africanized honey bee competitors colonized Panama in 1984. Cecropia deposited in the nest increased markedly after landscape-level vegetation disturbance. Pollen from Cavanillesia demonstrated that the foraging range encompassed 3 km2 and perhaps 500 plant species. Trigona corvina primarily foraged on plants with large inflorescences, consistent with foraging theory considering their aggressive behavior
Large-Range Movements of Neotropical Orchid Bees Observed via Radio Telemetry
Neotropical orchid bees (Euglossini) are often cited as classic examples of trapline-foragers with potentially extensive foraging ranges. If long-distance movements are habitual, rare plants in widely scattered locations may benefit from euglossine pollination services. Here we report the first successful use of micro radio telemetry to track the movement of an insect pollinator in a complex and forested environment. Our results indicate that individual male orchid bees (Exaerete frontalis) habitually use large rainforest areas (at least 42–115 ha) on a daily basis. Aerial telemetry located individuals up to 5 km away from their core areas, and bees were often stationary, for variable periods, between flights to successive localities. These data suggest a higher degree of site fidelity than what may be expected in a free living male bee, and has implications for our understanding of biological activity patterns and the evolution of forest pollinators
Topological structure of plant-bee networks in four Mexican environments
We analyzed the topological structure (e.g., links per species, connectance, core-periphery analyses, specialization, nestedness, modularity) of plant-bee interactions of four areas in Mexico. We used qualitative data (binary networks). Mexico exhibits a complex geography and community variation that can affect bee networks. Network architecture is variable within large spatial scales, thus our results should vary according to site characteristics (La Mancha and Totula in Veracruz, Carrillo Puerto in Quintana Roo, and the Tehuacan-Cuicatlan valley, in Puebla), type of vegetation, endemism, altitude, size of area sampled. Network topology varied among sites, and the presence of nested or modular patterns was analyzed for robustness to simulated species extinctions. The lowest species richness was recorded for the Quintana Roo site (15 plant, 25 bee species), and the highest for the Tehuacan-Cuicatlan valley site (88 plant, 231 bee species). There was a tendency to have more connected networks when species richness was low and networks with greater species richness had a higher number of interactions. The distribution of interactions differed between environments but not due to network size and all were significantly nested. The robustness to cumulative extinctions showed a different pattern at each site; the most robust network was at Carrillo Puerto, which also was the site with less species. Sites with more endemic species (e.g. Tehuacan) had more specialized interactions, and were more susceptible to extinction
Coupling of pollination services and coffee suitability under climate change
Climate change will cause geographic range shifts for pollinators and major crops, with global implications for food security and rural livelihoods. However, little is known about the potential for coupled impacts of climate change on pollinators and crops. Coffee production exemplifies this issue, because large losses in areas suitable for coffee production have been projected due to climate change and because coffee production is dependent on bee pollination. We modeled the potential distributions of coffee and coffee pollinators under current and future climates in Latin America to understand whether future coffee-suitable areas will also be suitable for pollinators. Our results suggest that coffee-suitable areas will be reduced 73–88% by 2050 across warming scenarios, a decline 46–76% greater than estimated by global assessments. Mean bee richness will decline 8–18% within future coffee-suitable areas, but all are predicted to contain at least 5 bee species, and 46–59% of future coffee-suitable areas will contain 10 or more species. In our models, coffee suitability and bee richness each increase (i.e., positive coupling) in 10–22% of future coffee-suitable areas. Diminished coffee suitability and bee richness (i.e., negative coupling), however, occur in 34–51% of other areas. Finally, in 31–33% of the future coffee distribution areas, bee richness decreases and coffee suitability increases. Assessing coupled effects of climate change on crop suitability and pollination can help target appropriate management practices, including forest conservation, shade adjustment, crop rotation, or status quo, in different regions
A Critical View of Colony Losses in Managed Mayan Honey-Making Bees (Apidae: Meliponini) in the Heart of Zona Maya
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