Cecropia is a genus of very common Neotropical plants known as guarumo (spanish) or embaúba (portuguese). They are very well known by their defensive mutualism with ants and generally thought to be wind-pollinated. But the reality is that pollination has never been studied in most cases.
It turns out that, hiding in plain sight, there are weevils intimately associated with flowers of Cecropia. This is the genus Udeus. Aline Lira is a PhD student at the Universidad Federal Rural de Pernambuco in Brazil, who I am co-advising, and she is currently working on the systematics, natural history and evolution of this genus.
Udeus eugnomoides in male flowers of Cecropia peltata in Panama.
The number of described species in the genus is certainly very small compared to the real existing diversity, and so far pretty much every new species of Cecropia that we sampled has resulted in a different species of Udeus.
It is appalling how rare these weevils are in collections, since in nature their host plants are extremely abundant and the weevils themselves are quite abundant on their flowers. Maybe because of their small size and colors blending well with the flower background? To encourage people to collect more samples, Aline has put together a guide available in Portuguese here: http://www.ppgea.ufrpe.br/sites/ppgea.ufrpe.br/files/entomonews_008.pdf
Basically, you can find adult weevils always in male inflorescences and, in some species of Cecropia, also in the female inflorescences. The larvae can be found inside branches of old male inflorescences. Because these are shed by the plant, this is the easiest way to sample them: find a decaying male inflorescence in the leaf litter, put in a container and wait a week for the adults to emerge.
If you are reading this text and find any Udeus in your backyard, please reach out!