It is pollinated by Ceratopogonid flies; these are the small, blood-sucking flies that pester humans and other mammals in the humid summer. The flowers of Aristolochia watsonii resemble a mouse's ear-translucent funnels with fur and veins-and give off a musty odor. The fly apparently expects to find a blood meal, and instead is trapped inside the flower tube overnight. During the night the flower releases pollen. The following morning the flower releases the pollen-covered fly. If the fly visits another flower it effects pollination.