-Sex and caste allocation by five stingless bee species was investigated. The study included species that build royal cells (RCP: Plebeia remota and Schwarziana quadripunctata) and species that do not (RCA: Melipona asilvai, M. bicolor and M. subnitida). Allocation to gynes, males and workers was assessed by linear regression slopes and simple ratios. RCP had higher allocation to males, and RCA had higher allocation to gynes and workers. In both groups, a negative correlation in males vs. workers suggested a prevalent opportunity cost, which may hinder colony growth and/or colony fission. stingless bees / Meliponini / sex ratio / worker production / numerical allocation

Abstract:For this work, we considered the results of four studies that sampled bees on flowers in the two main biomes of São Paulo State: Atlantic forest (3 locations) and 'cerrado' (4 locations). We found 276 species of bees belonging to 88 genera: 207 species and 78 genera in the Atlantic forest and 105 genera and 40 species in the 'cerrado' biome. Apidae family was the most represented in both biomes. In the sampled areas, bees visited 433 plant species: 361 in the Atlantic forest and 75 in the 'cerrado'.

-Stingless bees may produce both large queens and "miniature" queens, but the adaptive significance of this is uncertain. Using biometry and statistical analysis we determined the proportion of miniature queens in Plebeia remota that were either mated (14%) or virgin (45%). Mated queens were mostly normalsized which indicated that they were more successful. Nevertheless, the presence of miniature mated queens heading colonies confirmed that they also are viable. The egg-laying capacity of mated queens of different sizes was determined using colony exchange experiments. The results showed that egg laying is not influenced by size differences. Therefore, miniature mated queens may be as successful in laying eggs as normal-sized queens. Finally we discuss some ultimate hypotheses for why miniature queens are produced.queen size variation / miniature queen / egg laying / stingless bee / Plebeia remota

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