A pollination and breeding system study was conducted on a neotropical palm, Astrocaryum vulgare, in
Guyana, South America, to better understand its reproductive character evolution, and test the predictability of pollination
syndromes. The pollination syndrome approach was used because it integrates characteristics of flowers and their
pollinators into an evolutionary framework that allowed experimental testing of predictions. The flowers of A. vulgare
displayed traits that were typical of both beetle and wind pollination syndromes. The protogynous inflorescences
produced heat and odour during nocturnal anthesis, had numerous stamens with copious, light pollen, and were visited
by hordes of beetles that used the inflorescences as feeding, mating and oviposition sites. In contrast, some of these
features, such as numerous stamens with copious, light pollen, a high pollen to ovule ratio, and no obvious production
of visitor rewards, were also typical of the wind pollination syndrome. However, floral rewards appeared to be tissues
of the fleshy staminate petals and pollen that were readily devoured by the beetles. In addition to the Coleoptera, insect
visitors to A. vulgare inflorescences included several species of Hymenoptera, Diptera and Orthoptera. However, only
Nitidulidae and Curculionidae beetles were effective insect pollinators. Pollination treatments showed that wind pollination was possible, but fruit set was significantly higher for female flowers visited by beetles. Although a pollen/ovule ratio of 50 000:1 and outcrossing index confirmed an outcrossing breeding system, pollination experiments
suggested that A. vulgare had the potential for self pollination. Therefore, the breeding system might be best classified
as facultatively xenogamous (cross fertilizing). The predictive value of potential pollinator agents for A. vulgare was
inadequate because its floral traits were indicative of both cantharophilous and anemophilous pollination syndromes.