Pollination biology and reproductive ecology of critically endangered endemic <i>Campanula teucrioides</i> in western Anatolia

Campanula teucrioides Boiss. is a critically endangered species found in a single locality in western Turkey. Determining the population size of C. teucrioides and conducting reproductive biology studies are of great importance in determining the necessary strategy for the conservation of the species. The area where the plant distributed was determined and the number of individuals within the area was calculated. To determine its reproductive strategy, floral morphological measurements, flower opening mechanism, developmental stages, stigma receptivity, and pollen viability tests were conducted. The effects of cross‐ and self‐pollination on seed production were examined, and the self‐compatibility rate was assessed. Pollinator species visiting the flowers were identified through field observations. Campanula teucrioides is distributed in an area of 6.55 km 2 and has approximately 4296 individuals. Anthropogenic effects have destroyed 9.77% of the distribution area. Campanula teucrioides exhibits a mixed mating system, with a self‐incompatibility index of 0.3, indicating partial self‐incompatibility. Secondary pollen presentation occurs via sub‐terminal stylar presentation, and stigma receptivity begins before full anthesis. During the flower visitor observations, eight species belonging to six families were identified and it was determined that the number of visits of these species during the day was correlated with nectar parameters. Among these species, the most effective pollinator for C. teucrioides was determined to be Chelostoma campanularum , which performed 64.3% of the total visits. As a result, the mixed mating system of C. teucrioides and its 96.5% seed production success through allogamy demonstrate its high reproductive performance despite harsh subalpine conditions. However, the loss of part of its limited distribution area due to anthropogenic impacts over the past decade underscores the need to prioritize mitigating human‐induced threats in conservation strategies for this local endemic species.