Yucca Moth

Tegeticula yuccasella and the closely related Tegeticula and Parategeticula species are the yucca moths — small white moths that are the SOLE pollinators of yucca plants (genus Yucca, ~50 species across the Americas) and one of the most extreme obligate mutualisms in the natural world. The mutualism works as follows: a female yucca moth visits a yucca flower and uses specialized maxillary tentacles (a unique anatomical structure not found in any other moth) to actively collect pollen from the flower's anthers, packing it into a ball that she carries with her. She then flies to a DIFFERENT yucca plant, finds another flower, and inserts her ovipositor into the flower's ovary to lay 1-5 eggs. After laying eggs, she climbs up to the flower's stigma and DELIBERATELY PUSHES the collected pollen ball into the stigma — actively fertilizing the flower so that seeds will develop. Without this active pollen placement, the flower will not produce seeds, and her larvae (which feed on developing yucca seeds) will starve. The behavior is one of the only documented cases of 'insect agriculture' outside of the leaf-cutter ant fungus gardens. The relationship is obligate on both sides: yucca cannot reproduce without the yucca moth (the flowers have no nectar reward and only release pollen to the moth's specific manipulation), and yucca moth larvae cannot complete development on any other plant. The relationship has co-evolved for at least 40 million years and is one of the most-cited examples of pollinator-plant mutualism in evolutionary biology, alongside the fig-wasp / fig partnership.