Discrimination of Tanzanian stingless bee species (Hymenoptera, Apidae, Meliponini) based on nest characteristics

Stingless bees are a unique resource to Afrotropical ecosystems where they pollinate crops and natural vegetation, and produce honey which has medicinal powers. Studies on African stingless bees are limited partly due to difficulties in identifying them in the field. This study aimed to explore the use of nest characteristics as a simplified technique to discriminate Tanzanian stingless bee species. A total of 49 nests belonging to eight stingless bee species were studied in 15 locations. Qualitative and quantitative data on nesting sites, nest cavities, and architecture of nest entrances, brood rearing area and food storage area were collected and analyzed by comparison of means, hierarchical clustering and principal component analysis (PCA). We found that, differences in nest characteristics among stingless bee species reflected adaptations which enhanced various functions including insulation, ventilation, defense and survival. Four of the studied species were clearly separated on the dendrogram generated by Gower’s distance and PCA plot based on quantitative data of nest architecture. Qualitative data assisted the distinction of two other species which had similar nest architecture. The findings of this study suggest that nest characteristics can facilitate identification of stingless bee species in the field. We propose the development of taxonomic tools based on key nest characteristics to provide a practical and user-friendly approach which even personnel who lack scientific expertise can use to discriminate stingless bee species. Such tools would contribute to the advancement of stingless bee management, research and extension services.