Stingless bees in urban areas: low body size and high frequency of diploid males at mating congregations of Nannotrigona perilampoides (Hymenoptera: Meliponini) in Mérida, Yucatán, México

Abstract

In temperate regions of the world dominated by intensive agriculture, cities harbor a rich diversity and abundance of bee species, often exceeding those of the rural environment. In less industrialized tropical countries, in contrast, stressful conditions may exist in cities for bees with perennial colonies such as stingless bees because of the lack of resources such as amenity green spaces (flowers) and appropriate nesting sites. Yet, we currently lack studies on the ecology of bees in tropical urban areas to test this idea. Here, we compared the body size (as a possible indicator of floral resource supply) and the frequency of diploid males (as a measure of inbreeding) of a widespread stingless bee, Nannotrigona perilampoides , at mating congregations within the city of Merida, Yucatán, Mexico, and in surrounding rural areas. We found that males in Merida were significantly smaller compared with those in rural areas. While diploid males were found in both in the city and rural congregations, their frequency was significantly higher in urban sites. Our results suggest that the performance of colonies of N. perilampoides is poorer in tropical urban compared with rural sites, possibly as a consequence of limited resources and mating among a small number of colonies. We discuss the implications of these findings for the survival and fitness of stingless bees in the tropics.Urbanization / deforestation / microsatellite / heterozygosity / Meliponini / inbreeding

The Insecticide Imidacloprid Decreases Nannotrigona Stingless Bee Survival and Food Consumption and Modulates the Expression of Detoxification and Immune-Related Genes

“…Furthermore, this pesticide was found to be more toxic to the native stingless bee Nannnotrigona perilampoides compared to other pesticides, and N. perilampoides was more sensitive to imidacloprid than other stingless bee species [33]. An additional importance of N. perilampoides is that it is a widespread stingless bee species in Mexico, found both in rural and in urban environments [23,24]; furthermore, it has the potential to be used in commercial pollination [42]. It therefore represents an important model stingless bee species, whose sensitivity to imidacloprid deserves closer scrutiny.…”

“…However, agrochemical treatment is a frequent practice in the management of pest arthropods in many crops of these plant families [22]. In addition, urban areas can be home to several species of stingless bee [23] and, as a result, exposure to pesticides for the control of insect vectors of human pathogens can be frequent in these environments [24].…”