Western Olivaceous Flatbill

The western olivaceous flatbill (Rhynchocyclus aequinoctialis) is a species of bird in the family Tyrannidae, the tyrant flycatchers. It is found in Bolivia, Brazil, Colombia, Ecuador, Panama, Peru, and Venezuela. == Taxonomy and systematics == The western olivaceous flatbill was originally described in 1858 as Cyclorhynchus aequinoctialis. The author noted its resemblance to C. olivaceous, which later became the "olivaceous flatbill" (Rhynchocyclus olivaceous). What is now the western olivaceous flatbill was long treated as a subspecies of that olivaceous flatbill. Following a paper published in 2016 several taxonomic systems split the olivaceous flatbill into western and eastern species though some took until 2023 to do so. By the principle of priority the eastern retained the binomial Rhynchocyclus olivaceous. However, as of early 2025 the North and South American Classification Committees of the American Ornithological Society retain the unsplit olivaceous flatbill, though based on a 2021 publication the South American committee is seeking a proposal to split it into as many as four species. According to the International Ornithological Committee and the Clements taxonomy, the western olivaceous flatbill has these seven subspecies: R. a. bardus (Bangs & Barbour, 1922) R. a. mirus Meyer de Schauensee, 1950 R. a. flavus (Chapman, 1914)…