Spondias tuberosa Arruda, an endemic species of "caatinga", has a great economic importance, because its fruits are highly commercialized. Nevertheless, there are no researches concerning floral and pollination biology of this species, that would be important to agriculture research. The objective of this study was to analyse the reproductive phenology, floral biology and pollination of Spondias tuberosa, and to compare the similarity of its pollinators with those of Ziziphus joazeiro Mart., in the "caatinga". This study was carried out in the municipality of Boa Vista, Paraíba State, Brazil. The flowering and fruiting season occurred at the end of dry season and during the whole wet season, respectively. Spondias tuberosa is andromonoecious and possess hermaphrodites and male flowers on the same inflorescence. The flowers are white and have two groups of stamens. The hermaphrodite flowers have a pentacarpelar gynoecium with a single ovule while the male flowers present a pistiloid. Flower opening changes according to development stage of the inflorescence. The majority of hermaphrodite flowers open on the initial development stage. The anthesis began at 5:00h, lasting two days to hermaphrodite flowers and one day to male flowers. Eight species of wasps, six of bees and four of flies were registered visiting flowers of Spondias tuberosa. Scaptotrigona postica flavisetis Moure, Trigona fuscipennis Friese (Apidae) and Polybia ignobilis Haliday (Vespidae) were the mainly pollinators. The similarity between the pollinators of Spondias tuberosa and Ziziphus joazeiro was low, suggesting that the reproductive success of theses species was not affected by pollinator's share, despite the fact that flowering occur at the same time.
andromonoecy; "caatinga"; reproduction; Spondias tuberosa; umbuzeiro
