Distribution, nest architecture, and forage plants of an endemic Wallacean species of stingless bee Wallacetrigona incisa (Apidae: Meliponini) in Sulawesi, Indonesia

Abstract Wallacetrigona incisa is a Wallacean species endemic to Sulawesi Island, Indonesia. To protect natural colonies, their habitat must be kept stable. Hunting in natural habitats and moving colonies to unsuitable environments causes stress. Information on their habitat distribution has been revealed; however, information on their distribution still needs to be improved, and aspects of their ecology that are currently poorly understood need to be studied for conservation and utilization. We conducted research on their additional distribution in different locations in South and West Sulawesi provinces, nest architecture, and food plants by direct observation. Each nest was found, the GPS position was measured, habitat conditions were characterized, and pollen was collected to determine the forage plants. Twenty-seven living nests were recorded in South Sulawesi, and two in West Sulawesi. The most prominent distinctive nest architecture for the defense of the colony from damage by predation is the strong entrance covered with a thick, hard resin of the Agathis plant. From the analysis of pollen balls on the feet of bees, it was found that forage plants from 19 families and 38 types of pollen, and the three dominant species were Agathis celebica, Barringtonia asiatica, and Pigafetta elata. This finding is important for supporting the conservation of this Sulawesi endemic species.