Polinización y polinizadores en la vegetación de la planicie costera de Paraguaná, Estado Falcón, Venezuela / Pollination and pollinators in the vegetation of the coastal plain of Paraguaná, Falcón State, Venezuela

ABSTRACT

Pollination systems and plant-pollinator dynamics were studied for 51 plant species according to life form, vegetation type, and flowering phenology in the Paraguaná peninsula, Venezuela. A total of 43 species of floral visitors were recorded from which only 33 (76.7 per cent) were effective pollinators and ten only visitors. Pollinator fauna consisted only of insects. Six pollinating agent classes were identified in the area of study. Pollinating bees were the most important class (35.1 per cent), followed by butterflies (24.3 per cent) and flies (13.5 per cent). This trend was similar for the psamophilous and mangrove vegetation, but pollinating wasps were the third in importance in the littoral vegetation. Temporal distribution of pollinating agent classes showed a peak during the flowering peak, and during the lowest level of rainfall in the locality. Pollination systems were mostly polyphilous (62.7 per cent) followed by monophilous (27.4 per cent), and oligophilous species (7.8 per cent). This trend was found to be similar for the different vegetation types and life forms. In a similar way, pollinator agents were mainly polytropic (60.4 per cent), followed by monotropic (24.6 per cent) and oligotropic species (14.8 per cent). Plant species/pollinator species ratio was close to one for all vegetation types in the Paraguaná peninsula. Besides, the average number of pollinator species per plant species was 2.2, and the average number of plant species pollinated per insect species was 2.7. Plant species/pollinator species ratio and the average values of pollinator and plant species indicate a diffuse and symmetric relation between pollinator and plant species. These results are discussed in the context of the dynamics of pollination.