Nesting biology and social structure of Euglossa (Euglossa) townsendi Cockerell (Hymenoptera, Apidae, Euglossini)

Abstract

The nesting behavior of the euglossine bee Euglossa townsendi was studied on the campus of the University of São Paulo-Ribeirão Preto, SP, Brazil, from January 1994 to December 1999, using artificial nesting substrate and observation boxes. Twenty-one nests were founded during the study period, with the highest frequencies of nesting occurring during the hot, wet season. Each nest was founded by a single female and, after the completion of the last cell, she spent most of her time in the nest. The males left the nest immediately after emergence and did not return. Some females left the nest within a few days of eclosing, while others stayed in their natal nests and began to reactivate them. Reactivations were performed by a single female, by one or more females in the presence of the mother, by more than one female in the absence of the mother, and by more than one female in the presence of females that participated in the prior reactivation. According to behavior, the females were classified as forager/egg-laying and egg-laying females. The oviposition by egg-laying females was always preceded by oophagy. All of the forager/egg-laying and egg-laying females that were dissected had been inseminated. The behavior displayed by egg-laying females is characteristic of brood parasitism and fits the parental parasitism hypothesis developed as an alternative pathway by which insect sociality could have arisen. The behaviors displayed by E. townsendi, together with those reported for Euglossa cordata, show that both species have bionomic traits that resemble the conditions suggested as precursors of the origin of eusociality.Research article 401 activities and dissected. Each spermatheca was squashed between a slide and a coverslip, and examined under a microscope. Statistical analyses were performed using Statistica 5.0 (StatSoft, Inc.). Throughout the text, all means are given ± SD.

Nesting Biology of Euglossa dodsoni Moure (Hymenoptera: Euglossinae) in Panama

“…In many cases (e.g., Nests 12, 13, 15) we found cells containing very contrasting stages of development and in some cases even empty cells. The presence of used empty cells in nests with cells being provisioned suggests that the resident and its offspring could cohabit, as reported for other species of Euglossa (Augusto and Garofalo, 2004). Whether such cohabitation leads to any kind of social interactions is unknown and warrants further investigation.…”

“…Nest of many species are made of wax and resins mixed with plant material and other materials, creating a strong structure that provides protection against environmental fluctuations and predators (Roubik and Hanson, 2004). Most Euglossa females are solitary nesters, but multifemale nesting is facultative for some species (Soucy et al, 2003;Augusto and Garofalo, 2004). In E. hyacinthina, for example, all females that cohabit in a nest are capable or reproducing and there are no clear indications of dominance among the individuals, with sex ratios biased toward females (Soucy et al, 2003;Capaldi et al, 2007).…”

The Ecological Basis for Biogeographic Classification: an Example in Orchid Bees (Apidae: Euglossini)

“…For the purpose of categorization, social behavior was determined as follows: Aglae and Exaerete were classified as parasitic (Cameron 2004, Garófalo 2006, Nemésio and Silveira 2006, Eufriesea as solitary (Kimsey 1982, Cameron 2004, Garófalo 2006, Euglossa as communal-solitary (Eberhard 1989, Soucy et al 2003, Augusto & Garófalo 2004, and Eulaema as communal (Bennett 1965, Santos & Garófalo 1994, Cameron 2004). …”

“…Eufriesea Cockerell is predominantly solitary, although cooperative forms are reported (Kimsey 1982, Eberhard 1989, Garófalo 1994, Soucy et al 2003. More complex levels of cooperation exist in Eulaema Lepeletier and Euglossa Latreille (Bennett 1965, Santos & Garófalo 1994, Augusto & Garófalo 2004. Exaerete Hoffmannsegg and Aglae Lepeletier & Serville are obligate parasites of other euglossines (Roubik & Hanson 2004).…”

“…The available evidence strongly suggests that the euglossine bees are by no means strictly solitary (Soucy et al 2003, Augusto & Garófalo 2004, Garófalo 2006, Otero et al 2008, Cocom-Pech et al 2008.…”