Over the last decades, descriptions of tropical forests beetles have made a large taxonomic contribution in Coleoptera, but the mechanisms and rules explaining the species distribution and abundance in the tropics are still poorly understood. Adults of Mordellidae are phytophagous and feed on pollen, so distribution patterns of beetles at a fine scale responding to forest composition should reflect animal–plant ecological relations. Data collected from a canopy arthropod biodiversity study conducted in Ecuadorian Amazonian forests between January 1994 and July 2002 is here used for exploring spatial and temporal distribution patterns of beetles responding to tree species occurrence and microhabitat characteristics. Point maps of beetle distributions were produced at a scale of meters using ArcView and distribution patterns observed was tested against canopy variables, such as: tree species composition; strata structure; occurrence of dry leaves, lianas and epiphytes, and light measures. Mordellidae is very rich in species in the canopy of lowland tropical forests. Richness seems to be stable between seasons, but there is a great turn over in composition between seasons. A majority of species are restricted in distribution and this could be responding to high degree of host specialization. Using GIS techniques helps to set distribution information for beetles at a very fine scale that can be applied to planning inventory studies and making local conservation decisions.