Method for maintaining adult solitary bee Centris analis under laboratory conditions

Abstract

Although solitary bees represent at least 70% of bee species, most ecotoxicological studies on bees focus on social species and there are only a few species of solitary bees. One of the challenges in developing toxicological studies on solitary bees is the lack of protocols for maintaining these species under laboratory conditions. This study aimed to develop a method to maintain adult individuals of the solitary bee Centris analis under controlled conditions. Six models of cages with adaptations for food identification and resting areas were tested based on cages used for Apis mellifera and Osmia bicornis. With this in mind, we placed one individual of Centris analis in each cage and set the temperature at 28°C. Cage models with survival higher than 50% of individuals were used to measure the influence of photoperiod, training and concentration of food in bee adaptation and longevity. Cages containing a wood cube and an artificial fabric flower supported the survival of 75% of captive bees for longer than 30 days at 28°C. Bee survival rate was higher in the absence of photoperiod. This work showed the importance of an acclimatization period of 3 days for C. analis and described a feasible method for future studies evaluating the effects of pesticide effects on solitary bees under laboratory conditions.

Sensitivity of the Neotropical Solitary Bee Centris analis F. (Hymenoptera, Apidae) to the Reference Insecticide Dimethoate for Pesticide Risk Assessment

“…The oil‐collecting bee C. analis is a cavity‐nesting, solitary bee (Supporting Information, Figure S1), widely distributed in South America, from Mexico to Brazil (Moure, 2012). This species was selected for our study because it is a multivoltine species with nesting activities in natural and artificial cavities (Moure‐Oliveira et al, 2017; Silva et al, 2017) and because there is a preexisting method for the maintenance of adult organisms under laboratory conditions (Tadei et al, 2022).…”

“…After the emergence of the bees, 10 females and 13 males of different nests were used to calculate the bee fresh weight. For the other newly emerged bees, each bee was transferred to a ventilated, transparent plastic cage containing a wooden cube and an artificial flower around the microtube feeder (500 µl), according to the methodology described in Tadei et al (2022). Acclimatization under laboratory conditions occurred for at least 4 days (Figure 1), where individuals were fed with 35% w/w sucrose solution and kept at 28 ± 2 °C, 75% ± 10% humidity, with the absence of light inside the incubator.…”