Tropical Ecology and Conservation [Monteverde Institute]

Alternative Title

Los efectos de los factores intrínsecos y extrínsecos respecto a las visitas florales de Xanthosoma undipes en Monteverde, Costa Rica


Kirsten Martin



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Publication Date

November 2008


Both intrinsic and extrinsic floral characteristics exert important influences on floral visitation. The average distance between flowering plants, the number of flowering plants, and the spadix temperature were assessed to determine the influence of these intrinsic and extrinsic floral factors on floral visitation in Xanthosoma undipes in Monteverde Costa Rica. Observations were made for seven nights in which the distances between all flowering plants, abundances of all morphospecies of arthropods present and spadix temperatures were taken. Both the number of plants in flower and the average distance between flowers did appear to have an affect on flower visitation among pollinators. As the number of male inflorescences open in a night increased, the number of scarabs per inflorescence tended to decrease (p = 0.0687). It was also found that as the average distance between plants increased, the number of scarabs per inflorescence increased (p = 0.0374). On the other hand, arthropod abundances showed no correlation with either the number of plants in flower (p = 0.1911) or the average distance between flowering plants (p=0.1881), which suggests a lower degree of specialization among interlopers than the Cyclocephala pollinators. The inflorescences sexual identity, an intrinsic factor, did have an affect on visitor composition. Diversity in male inflorescences was significantly higher than diversity in female inflorescences (H’males=1.5097, H’females=0.6466. t= 15.826, F = 1.964). This study showed that both intrinsic and extrinsic factors are important in floral visitation in X. undipes, and different floral factors have differing affects on interloper and scarab visitation. Understanding the effects of both intrinsic and extrinsic factors in floral visitation is important because plant pollination directly affects plant reproduction and therefore directly affects plant fitness.


Tanto las características florales intrínsecas como extrínsecas ejercen influencias importantes en la visitación floral. La distancia promedio entre las plantas con flores, el número de flores por planta y la temperatura del espádice fueron tomados para medir la influencia de estos factores intrínsecos y extrínsecos en la visitación floral en Xanthosoma undipes en Monteverde, Costa Rica.


Flowers--Morphology, Species diversity, Scarabs, CIEE Fall 2008

Palabras claves

Flores--Morfología, Diversidad de especies, Escarabajos, CIEE Otoño 2008


10 pages

Geographic Location

Monteverde Cloud Forest Reserve (Costa Rica)

Ubicación geográfica

Reserva Biológica Bosque Nuboso Monteverde (Costa Rica)

Holding Location

Monteverde Institute


English; Spanish

Media Type



Digital Only





The effects of intrinsic and extrensic factors on floral visitation of Xanthosoma undipes in Monteverde, Costa Rica



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