Elaenia sordida is a small-headed, crestless elaenia. A 2022 study in northeastern Argentina recorded foraging in scrub and secondary forest, including fruit feeding.
It has a conspicuously small head and lacks a crest.
From July to September 2022, birds were recorded foraging in scrub and secondary forest at Rincón de Santa María Reserve, Corrientes Province. Fruit feeding was also observed.
An extinction-risk assessment has not been added yet.