Pollination of the endangered palm Attalea amygdalina (Arecaceae) in Colombia: Palm-pollinator interactions in a severely altered habitat

We studied the pollination ecology of the endangered palm Attalea amygdalina (Arecaceae) in the Andes of Colombia, in an area mostly converted into coffee plantations. A. amygdalina has a short underground stem, and large staminate and androgynous (functionally pistillate) inflorescences, which are borne near ground level, and open during the day. This monoecious, but functionally dioecious palm, has morphological and phenological characteristics associated with beetle pollination. The main pollinators are small nitidulid beetles, which developed part of their reproductive cycles (mating, ovipositing and larvae feeding) in the staminate flowers. The androgynous inflorescences offer no reward, and they attract insects by a combination of visual and olfactory mimicry. The floral scent of both types of inflorescences is dominated by two isomers of conophtorin. Scent production in the inflorescence buds is associated with thermogenesis, and temperature within the buds rises up to 10°C above ambient temperature. Plant-pollinator interactions of this palm, which survives among coffee plantations, are similar to those found in other species of the genus that grow in forest or in less disturbed habitats, in all cases involving small nitidulids that reproduce among the flowers. The persistense of the palm-beetle interaction in a severely altered habitat shows the close relationship that exists between nitidulids and palms.