Sharp-billed Treehunter

The sharp-billed treehunter (Heliobletus contaminatus), sometimes called the sharp-billed xenops, is a species of bird in the Furnariinae subfamily of the ovenbird family Furnariidae. It is found in Argentina, Brazil, Paraguay, and Uruguay. == Taxonomy and systematics == The sharp-billed treehunter is assigned two subspecies, the nominate H. c. contaminatus (Berlepsch, 1885) and (as of 2023) H. c. camargoi (Cardoso da Silva & Stotz, 1992). However, there is some confusion about the subspecific epithets of the subspecies, and one or both might be changed. In recognition of that possibility, BirdLife International's Handbook of the Birds of the World gives H. c. camargoi the trinomial "Heliobletus contaminatus [new name]". One author included genus Heliobletus within Xenops, as the sharp-billed treehunter's plumage is very similar to those of some Xenops species. Genetic data refute this treatment and find that it belongs in Heliobletus and is sister to genus Philydor. The sharp-billed treehunter is the only member of genus Heliobletus. However, one author states that "[a]n undescribed ''Heliobletus sp. occurs in SE Bahia [Brazil]". Recordings of this undescribed taxon have been made, and it has been found in the Serra do Lontras. == Description == The sharp-billed treehunter is 12 to 13 cm…