Ant pollination in Brazilian savanna

Ant–plant associations are widely diverse and distributed throughout the world, leading to complex ecological networks. Regarding ant–plant mutualism, ant pollination is a very rare interaction and few studies have shown the role of ants as pollinators. Del-Claro et al. aimed to evaluate the role of ants as effective pollinators of Paepalanthus lundii (Eriocaulaceae) in a Brazilian savanna.

The authors observed a relationship between seed production and ant visits; Camponotus crassus was the most frequent floral visitor and the most effective pollinator. Also, they observed a statistical difference between the numbers of male and female flowers produced, with a greater number of male flowers. Furthermore, P. lundii presented flowering asynchrony, with 12 different types of maturation sequence, which indicates a cross-pollination system. Lastly, Del-Claro and colleagues observed an overlap of the greatest abundance of C. crassus and the time of plant stigmatic receptivity, and a pattern of non co-occurrence of ants, which shows the pollinator role of this ant.

The study provides evidence that previous generalizations neglecting the importance of ants as pollinators are wrong. The Brazilian savanna can reveal a lot about the ant-pollination syndrome, since this environment presents peculiar characteristics related to this association. Thus, this study has great significance for the understanding of the ant-pollination syndrome, and for the understanding of the complex ecological networks present in these dry arid systems.